Wilderness Terrain

In the great outdoors, dragons cross the sky, looking for prey on the ground, while tribes of hobgoblins stalk their own victims. An ankheg bursts forth from the earth, and monstrous spiders drop from the trees.

Adventures and encounters outdoors can be as interesting as those underground, but they're different in many ways. Characters have greater freedom to roam. In a dungeon, characters are constrained by the doors and hallways available to them, but in a forest, they can travel in any direction they please.

The open wilderness can be liberating for the players, and it demands that the DM be flexible. You don't have to have every 5-foot square of the Abbor-Alz Mountains mapped before the adventure begins, but you should be able to draw the terrain in the immediate area when the red dragon roars out of the sky. Furthermore, you should know - in general terms, at least - what the characters will find if they cross that ridge or ford that stream.

A second difference between wilderness adventures and dungeon adventures is the possibility of retreat. In a dungeon, the PCs can generally retreat and recuperate without too much difficulty. But the wilderness is by definition far from the comforts of civilization, so the characters have to rely more on their own resources. There probably isn't a friendly temple full of healers in the middle of the trackless swamp the characters are fighting their way through, so the PC cleric will have to handle all the party's healing. There's no inn, so some characters will have to stay awake and keep watch while the other characters sleep. And if the characters are beset by foes, they have no safe place to run to - or at least no safe place nearby

Finally, wilderness adventures differ from dungeon ones because the wilderness is often ancillary to the characters' larger purpose. Wilderness adventures usually involve travel through the wild to a specific destination, not exploration of the wilderness for its own sake. A dungeon is a place you travel to, but the wilderness is a place you travel through. Characters are less inclined to linger without a good reason, because they're usually on their way to someplace else.

For obvious reasons, doors, floors, and walls are few and far between in the wilderness. Instead the characters will have to contend with everything from towering trees to quicksand as they make their way through the wilderness. The kinds of dangers they'll face depend on the terrain (forest, mountain, and so on) and climate (hot, temperate, or cold).

Getting Lost

There are many ways to get lost in the wilderness. Following an obvious road, trail, or feature such as a stream or shoreline prevents any possibility of becoming lost, but travelers striking off cross-country may become disoriented - especially in conditions of poor visibility or in difficult terrain.

Poor Visibility: Any time characters cannot see at least 60 feet in the prevailing conditions of visibility, they may become lost. Characters traveling through fog, snow, or a downpour might easily lose the ability to see any landmarks not in the immediate vicinity. Similarly, characters traveling at night may be at risk, too, depending on the quality of their light sources, amount of moonlight, and whether they have darkvision or low-light vision.

Difficult Terrain: Any character in forest, moor, hill, or mountain terrain may become lost if he or she moves away from a trail, road, stream, or other obvious path or track. Forests are especially dangerous because they obscure far-off landmarks and make it hard to see the sun or stars.

Chance to Get Lost: if conditions exist that make getting lost a possibility, the character leading the way must succeed on a Survival check or become lost. The difficulty of this check varies based on the terrain, the visibility conditions, and whether or not the character has a map of the area being traveled through. Refer to the table below and use the highest DC that applies.

 Survival DC
Moor or hill, map6
Mountain, map8
Moor or Hill, no map10
Poor visibility12
Mountain, no map12

A character with at least 5 ranks in Knowledge (geography), or Knowledge (local) pertaining to the area being traveled through gains a +2 bonus on this check.

Check once per hour (or portion of an hour) spent an local or overland movement to see if travelers have become lost. In the case of a party moving together, only the character leading the way makes the check. (Tip: Make this check in secret, since the characters may not realize that they're lost right away).

Effects of Being lost: If a party becomes lost, it is no longer certain of moving in the direction it intended to travel. Randomly determine the direction in which the party actually travels during each hour of local or overland movement. The characters' movement continues to be random until they blunder into a landmark they can't miss, or until they recognize that they are lost and make an effort to regain their bearings.

Recognizing that you're lost: Once per hour of random travel, each character in the party may attempt a Survival check (DC 20, -1 per hour of random travel) to recognize that they are no longer certain of their direction of travel. Some circumstances may make it obvious that the characters are lost; if they expected to reach a certain spot within an hour but three or four hours pass by with no sign of their destination, that's a bad sign.

Setting a New Course: A lost party is also uncertain of determining in which direction it should travel in order to reach a desired objective - even an objective such as "the point where we left the road and went off into these dratted woods." Determining the correct direction of travel once a party has become lost requires a Surviva1 check (DC 15, +2 per hour of random travel). If a character fails this check, he chooses a random direction as the correct direction for resuming travel. (Tip: Again, this is a check that should make in secret. The lost characters may think they know the way to travel after regaining their bearings, but could be entirely wrong again.)

Once the characters are traveling along their new course, correct or incorrect, they may get lost again, if the conditions still make it possible for travelers to become lost, check once per hour of travel as described in Chance to Get Lost, above, to see if the party maintains its new course or begins to move at random again.

Conflicting Directions: It's possible that several characters may attempt to determine the right direction to proceed after becoming lost. That's just fine. You make a Survival check for each character in secret, then tell the players whose characters succeeded the correct direction in which to travel, and tell the players whose characters failed a random direction they think is right. (Tip: A few extraneous die rolls behind your screen might make it less apparent which characters are right and which characters are wrong.)

Regaining Your Bearings: There are several ways to become unlost. First, if the characters successfully set a new course and follow it to the destination they're trying to reach, they're not lost anymore. Second, the characters through random movement might run into an unmistakable landmark. Third, if conditions suddenly improve - the fog lifts or the sun comes up - lost characters may attempt to set a new course, as described above, with a +4 bonus on the Survival check. Finally, magic such as find the path may make their course clear.

Forest Terrain

Forest terrain can be divided into three categories: sparse, medium, and dense. An immense forest could have all three categories within its borders, with more sparse terrain at the outer edge of the forest and dense forest at its heart.

The table below describes in general terms how likely it is that given square has a terrain element in it. You shouldn't roll for that square. Instead, use the percentages in the table below to guide the maps you create.

Forest Terrain Features
 Category of Forest
Typical trees50%70%80%
Massive trees-10%20%
Light undergrowth50%70%50%
Heavy undergrowth - 20%50%
Sample Temperate Forest Encounter Table (EL 6)
d%EncounterAverage EL
01-041d4+3 dryads8
05-101 treant8
11-165th-level lizardfolk druid NPC and 2 centaurs7
17-191 nymph7
20-251d4 unicorns7
26-331d6+1 wolves7
34-431d4 centaurs6
44-511d4 dire wolves6
52-611d3 owlbears6
62-691d3 pixies6
70-731 ghast (ghoul) and 2 ghouls5
74-795th-level gnoll ranger NPC5
80-851d4+1 satyrs5
86-881d4+1 owlbear skeletons5
89-931 wraith5
94-972 black bears (animal)4
98-1001 wereboar (lycanthrope)4

Trees: The most important terrain element in a forest is the trees, obviously. Place a dot in the center of each square that you decide has a tree in it, and don't worry about the tree's exact location within the square. A creature standing in the same square as a tree gains a +2 bonus to Armor Class and a +1 bonus on Reflex saves (these bonuses don't stack with cover bonuses from other sources). The presence of a tree doesn't otherwise affect a creature's fighting space, because it's assumed that the creature is using the tree to its advantage when it can. The trunk of a typical tree has AC 4, hardness 5, and 150 hp, A DC 15 Climb check is sufficient to climb a tree.

Medium and dense forests have massive trees as well. These take up an entire square and provide cover to anyone behind them. They have AC 3, hardness 5, and 600 hp. Like their smaller counterparts, it takes a DC 15 Climb check to climb them.

Undergrowth: Vines, roots, and short bushes cover much of the ground in a forest. A space covered with light undergrowth costs 2 squares of movement to move into, and it provides concealment.

Undergrowth increases the DC of Tumble and Move Silently checks by 2 because the leaves and branches get in the way

Heavy undergrowth costs 4 squares of movement to move into, and is provides concealment with a 30% miss chance (instead of the usual 20%). It increases the DC of Tumble and Move Silently checks by 5. Heavy undergrowth is easy to hide in, granting a +5 circumstance bonus on Hide checks. Running and charging are impossible.

Squares with undergrowth are often clustered together. Undergrowth and trees aren't mutually exclusive; it's common for a 5-foot square to have both a tree and undergrowth.

Forest Canopy: it's common for elves and other forest dwellers to live on raised platforms far above the surface floor. These wooden platforms generally have rope bridges between them. To get to the treehouses, characters generally ascend the trees' branches (Climb DC 15), use rope ladders (Climb DC 0), or take pulley elevators (which can be made to rise a number of feet equal to a Strength check, made each round, as a full-round action). Creatures on platforms or branches in a forest canopy are considered to have cover when fighting creatures on the ground, and in medium or dense forests they have concealment as well.

Other Forest Terrain Elements: Fallen logs generally stand about 3 feet high and provide cover just as low walls do. They cost 5 feet of movement to cross. Forest streams are generally 5 to 10 feet wide and no more than 5 feet deep. Pathways wind through most forests, allowing normal movement and providing neither cover nor concealment. These paths are less common in dense forests, but even unexplored forests will have occasional game trails.

Stealth and Detection in a Forest: In a sparse forest, the maximum distance at which a Spot check for detecting the nearby presence of others can succeed is 3d6x10 feet. In a medium forest, this distance is 2d5x10 feet, and in a dense forest it is 2d6x10 feet.

Because any square with undergrowth provides concealment, it's usually easy for a creature to use the Hide skill in the forest. Logs and massive trees provide cover, which also makes hiding possible.

The background noise in the forest makes Listen checks more difficult, increasing the DC of the check by 2 per 10 feet, not 1 (but note that Move Silently is also more difficult in undergrowth).

Forest Fires (CR 6)

Most campfire sparks ignite nothing, but if conditions are dry, winds are strong, or the forest floor is dried our and flammable, a forest fire can result. lightning strikes often set trees afire and start forest fires in this way. Whatever the cause of the fire, travelers can get caught in the conflagration.

A forest fire can be spotted from as far away as 2d6x100 feet by a character who makes a Spot check, treating the fire as a Colossal creature (reducing the DC by 16). If all characters fail their Spot checks, the fire moves closer to them. They automatically see it when it closes to half the original distance.

Characters who are blinded or otherwise unable to make Spot checks can feel the hear of the fire (and thus automatically "spot" it) when it is 100 feet away.

The leading edge of a fire (the downwind side) can advance faster than a human can run (assume 120 feet per round for winds of moderate strength). Once a particular portion of the forest is ablaze, it remains so for 2d4x10 minutes before dying to a smoking smolder. Characters overtaken by a forest fire may find the leading edge of the fire advancing away from them faster than they can keep up, trapping them deeper and deeper in its grasp. Within the bounds of a forest fire, a character faces three dangers: heat damage, catching on fire, and smoke inhalation.

Heat Damage: Getting caught within a forest fire is even worse than being exposed to extreme heat (see Heat Dangers). Breathing the air causes a character to take 1d6 points of damage per round (no save). In addition, a character must make a Fortitude save every S rounds (DC 15, +1 per previous check) or take 1d4 points of nonlethal damage. A character who holds his breath can avoid the lethal damage, but not the nonlethal damage. Those wearing heavy clothing or any sort of armor take a -4 penalty on their saving throws. In addition, those wearing metal armor or coming into contact with very hot metal are affected as if by a heat metal spell).

Catching on Fire: Characters engulfed in a forest fire are at risk of catching on fire when the leading edge of the fire overtakes them, and are then at risk once per minute thereafter (see Catching on Fire).

Smoke Inhalation: Forest fires naturally produce a great deal of smoke. A character who breathes heavy smoke must make a Fortitude save each round (DC 15, +1 per previous check) or spend that round choking and coughing. A character who chokes for 2 consecutive rounds takes 1d6 points of nonlethal damage. Also, smoke obscures vision, providing concealment to characters within it.

Marsh Terrain

Two categories of marsh exist: relatively dry moors and watery swamps. Both are often bordered by lakes (described in Aquatic Terrain), which effectively are a third category of terrain found in marshes.

The table below describes terrain features found in marshes. The percentages are indicative of typical marsh terrain and don't represent the exact chance that a given square will contain the terrain element.

Marsh Terrain Features
 Marsh Category
Shallow bog20%40%
Deep bog5%20%
Light undergrowth30%20%
Heavy undergrowth10%20%
Sample Temperate Marsh Encounter Table (EL 9)
d%EncounterAverage EL
01-071 eleven-headed hydra10
08-111d3 mohrgs10
12-151 young adult black dragon9
16-191d4+2 5th-level kobold sorcerer NPCs9
20-301d3 chuuls9
31-381d3 medusas9
39-451d4+2 5th-level goblin rogue NPCs9
46-531d3 spectres9
54-631d4 will-o'-wisps9
64-701d4 gray render zombies9
71-811 gray render8
82-911 hag covey (sea hag, annis, green hag)8
92-972d4 harpies8
98-1001 shambling mound6

Bogs: If a square is part of a shallow bog, it has deep mud or standing water of about 1 foot in depth. It costs 2 squares of movement to move into a square with a shallow bog, and the DC of Tumble checks in such a square increases by 2.

A square that is part of a deep bog has roughly 4 feet of standing water. It costs Medium or larger creatures 4 squares of movement to move into a square with a deep bog, or characters can swim if they wish. Small or smaller creatures must swim to move through a deep bog. Tumbling is impossible in a deep bog.

The water in a deep bog provides cover for Medium or larger creatures. Smaller creatures gain improved cover (+8 bonus to AC, +4 bonus on Reflex saves). Medium or larger creatures can crouch as a move action to gain this improved cover. Creatures with this improved cover take a -10 penalty on attacks against creatures that aren't underwater.

Deep bog squares are usually clustered together and surrounded by an irregular ring of shallow bog squares.

Both shallow and deep bogs increase the DC of Move Silently checks by 2.

Undergrowth: The bushes, rushes, and other tall grasses in marshes function as undergrowth does in a forest (see above). A square that is part of a bog does not also have undergrowth.

Quicksand: Patches of quicksand present a deceptively solid appearance (appearing as undergrowth or open land) that may trap careless characters, A character approaching a patch of quicksand at a normal pace is entitled to a DC 8 Survival check to spot the danger before stepping in, but charging or running characters don't have a chance to detect a hidden bog before blundering in. A typical patch of quicksand is 20 feet in diameter; the momentum of a charging or running character carries him or her 1d2x5 feet into the quicksand.

Effects of Quicksand: Characters in quicksand must make a DC 11 Swim check every round to simply tread water in place, or a DC 15 Swim check to move 5 feet in whatever direction is desired. If a trapped character fails this check by 5 or more, he sinks below the surface and begins to drown whenever he can no longer hold his breath (see the Swim skill description, and Drowning).

Characters below the surface of a bog may swim back to the surface with a successful Swim check (DC 15 +1 per consecutive round of being under the surface).

Rescue: Pulling out a character trapped an quicksand can be difficult. A rescuer needs a branch, spear haft, rope, or similar tool that enables him to reach the victim with one end of it. Then he must make a DC 15 Strength check to successfully pull the victim, and the victim must make a DC to Strength check to hold onto the branch, pole, or rope. If the victim fails to hold on, he must make a DC 15 Swim check immediately to stay above the surface. If both checks succeed, the victim is pulled 5 feet closer to safety.

Hedgerows: Common in moors, hedgerows are tangles of stones, soil, and thorny bushes.

Narrow hedgerows function as low walls, and it takes 15 feet of movement to cross them.

Wide hedgerows are more than 5 feet tall and take up entire squares. They provide total cover, just as a wall does. It takes 4 squares of movement to move through a square with a wide hedgerow; creatures that succeed on a DC 10 Climb check need only 2 squares of movement to move through the square.

Other Marsh Terrain Elements: Some marshes, particularly swamps, have trees just as forests do, usually clustered in stands. Paths lead across many marshes, winding to avoid bog areas. As in forests, paths allow normal movement and don't provide the concealment that undergrowth does.

Stealth and Detection in a Marsh: in a moor, the maximum distance at which a Spot check for detecting the nearby presence of others can succeed is 6d6x10 feet. In a swamp, this distance is 2d8x10 feet.

Undergrowth and deep bogs provide plentiful concealment, so it's easy to hide in a marsh.

A marsh imposes no penalties on listen checks, and using the Move Silently skill is more difficult in both undergrowth and bogs.

Hills Terrain

A hill can exist in most other types of terrain, but hills can also dominate the landscape. Hills terrain is divided into two categories: gentle hills and rugged hills. Hills terrain often serves as a transition zone between rugged terrain such as mountains and flat terrain such as plains.

Hills terrain requires extra forethought on your part because players will naturally want to know which direction is uphill. The table below indicates typical percentages of gradual and steep slopes in hills terrain but you'll want to draw your map carefully so uphill and downhill are clear and logical. The percentages below include no provision for flat space, but you may want the tops of your hills and the bottoms of your valleys to have at least a few squares of flat space.

Hills Terrain Features
 Hills Category
 Gentle HillRugged Hill
Gradual slope75%40%
Steep slope20%50%
Light Undergrowth15%15%
Sample Temperate Hills Encounter Table (EL 5)
d%EncounterAverage EL
01-021 young copper dragon7
03-051 bulette7
06-091 hill giant7
10-171d3 displacer beasts6
18-271d3 griffons6
28-341 wyvern6
35-445th-level human bard NPC5
45-581 ogre and 1d4+2 hobgoblin warriors5
59-681d3 ogre zombies5
69-771 rast5
78-851d3 wightsS
86-951d3 hippogriffs4
96-1001 doppelganger3

To draw hills terrain decide where you want your hill tops and valleys to be, then surround them with rings of gradual and steep slope squares. If you use cliffs, put them next to or within steep slope squares. Finally, draw arrows pointing downhill.

Gradual Slope: This incline isn't steep enough to affect movement, but characters gain a +1 bonus on melee attacks against foes downhill from them.

Steep Slope: Characters moving uphill (to an adjacent square of higher elevation) must spend 2 squares of movement to enter each square of steep slope. Characters running or charging downhill (moving to an adjacent square of lower elevation) must succeed on a DC 10 Balance check upon entering the first steep slope square. Mounted characters make a DC 10 Ride check instead. Characters who fail this check stumble and must end their movement 1d2x5 feet later. Characters who fail by 5 or more fall prone in the square where they end their movement.

A steep slope increases the DC of Tumble checks by 2.

Cliff: A cliff typically requires a DC 15 Climb check to scale and is 1d4x10 feet tall, although the needs of your map may mandate a taller cliff. A cliff isn't perfectly vertical, taking up 5-foot squares if it's less than 30 feet tall and 10-foot squares if it's 30 feet or taller.

Light Undergrowth: Sagebrush and other scrubby bushes grow on hills, although they rarely cover the landscape as they do in forests and marshes, light undergrowth provides concealment and increases the DC of Tumble and Move Silently checks by 2.

Other Hills Terrain Elements: Trees aren't out of place in hills terrain, and valleys often have active streams (5 to 10 feet wide and no more than 5 feet deep) or dry streambeds (treat as a trench 5 to 10 feet across) in them, if you add a stream or streambed, remember that water always flows downhill.

Stealth and Detection in Hills: in gentle hills, the maximum distance at which a Spot check for detecting the nearby presence of others can succeed is 2d10x10 feet. In rugged hills, this distance is 2d6x10 feet.

Hiding in hills terrain can be difficult if there isn't undergrowth around. A hilltop or ridge provides enough cover to hide from anyone below the hilltop or ridge.

Hills don't affect listen or Move Silently checks.

Mountain Terrain

The three mountain terrain categories are alpine meadows, rugged mountains, and forbidding mountains. As characters ascend into a mountainous area, they're likely to face each terrain category in turn, beginning with alpine meadows, extending through rugged mountains, and reaching forbidding mountains near the summit.

To draw a map for mountain terrain, use the percentages in the table below to arrange the terrain elements. As with hills terrain, you'll want to pay close attention to uphill and downhill, identifying the direction of descent on slopes. Gentle slopes, steep slopes, cliffs, and chasms are mutually exclusive. Either of the slope types may have undergrowth, scree, or dense rubble on it.

Mountains have an important terrain element, the rock wall, that is marked on the border between squares rather than taking up squares itself. After you draw the other terrain elements on the map, add rock walls, placing them within or adjacent to steep slopes and cliffs.

Mountain Terrain Features
 Mountain Category
 Alpine MeadowRuggedForbidding
Gradual slope50%25%15%
Steep slope40%55%55%
Chasm - 5%10%
Light undergrowth - 20%10%
Scree - 20%30%
Dense rubble - 20%30%
Sample Cold Mountains Encounter Table (EL 11)
d%EncounterAverage EL
01-041 beholder13
05-071 young adult silver dragon13
08-191d3 10th-level half-orc barbarian NPCs12
20-291 devourer11
30-471d3 frost giants11
48-581 d4 greater shadows11
59-751 troll hunter11
76-8810th-level drow wizard NPC and 1 shield guardian11
89-1002d4 trolls9

Gradual and Steep Slopes: These function as described in Hills Terrain.

Cliff: These terrain elements also function like their hills terrain counterparts, but they're typically 2d6x10 feet tall. Cliffs taller than 80 feet take up 20 feet of horizontal space.

Chasm: Usually formed by natural geological processes, chasms function like pits in a dungeon setting. Chasms aren't hidden, so characters won't fall into them by accident (although bull rushes are another story). A typical chasm is 2d4x10 feet deep, at least 20 feet long, and anywhere from 5 feet to 20 feet wide. It takes a DC 15 Climb check to climb out of a chasm.

In forbidding mountain terrain, chasms are typically 2d8x10 feet deep.

Light Undergrowth: This functions as described in Forest Terrain.

Scree: A field of shifting gravel, scree doesn't affect speed, but it can be treacherous on a slope. The DC of Balance and Tumble checks increases by 2 if there's scree on a gradual slope and by 5 if there's scree on a steep slope. The DC of Move silently checks increases by 2 if the scree is on a slope of any kind.

Dense Rubble: The ground is covered with rocks of all sizes. It costs 2 squares of movement to enter a square with dense rubble. The DC of Balance and Tumble checks on dense rubble increases by 5, and the DC of Move Silently checks increases by +2.

Rock Wall: A vertical plane of stone, rock walls require DC 25 Climb checks to ascend. A typical rock wall is 2d4x10 feet tall in rugged mountains and 2d8x10 feet tall in forbidding mountains. Rock walls are drawn on the edges of squares, not in the squares themselves.

Cave Entrance: Found in cliff and steep slope squares and next to rock walls, cave entrances are typically between 5 and 20 feet wide and 5 feet deep. Beyond the entrance, a cave could be anything from a simple chamber to the entrance to an elaborate dungeon. Caves used as monster lairs typically have 1d3 rooms that are 1d4x10 feet across.

Other Mountain Terrain Features: Most alpine meadows begin above the tree line, so trees and other forest elements are rare in the mountains. Mountain terrain can include active streams (5 to 10 feet wide and no more than 5 feet deep) and dry streambeds (treat as a trench 5 to 10 leer across). Particularly high-altitude areas tend to be colder than the lowland areas that surround them, so they may be covered in ice sheets (described cold).

Stealth and Detection in Mountains: As a guideline, the maximum distance in mountain terrain at which a Spot check for detecting the nearby presence of others can succeed is 4d10x10 feet. Certain peaks and ridgelines afford much better vantage points, of course, and twisting valleys and canyons have much shorter spotting distances. Because there's little vegetation to obstruct line of sight, the specifics on your map are your best guide for the range at which an encounter could begin.

As in hills terrain, a ridge or peak provides enough cover to hide from anyone below the high point.

It's easier to hear faraway sounds in the mountains. The DC of listen checks increases by 1 per 20 feet between listener and source, not per 10 feet.

Avalanches (CR 7)

The combination of high peaks and heavy snowfalls means that avalanches are a deadly peril in many mountainous areas. While avalanches of snow and ice are common, it's also possible to have an avalanche of rock and soil.

An avalanche can be spotted from as far away as 1d10x500 feet downslope by a character who makes a DC 20 Spot check, treating the avalanche as a Colossal creature. If all characters fail their Spot checks to determine the encounter distance, the avalanche moves closer to them, and they automatically become aware of it when it closes to half the original distance.

It's possible to hear an avalanche coming even if you can't see it. Under optimum conditions (no other loud noises occurring), a character who makes a DC 15 listen check can hear the avalanche or landslide when it is 1d6x500 feet away. This check might have a DC of 20, 25, or higher in conditions where hearing is difficult (such as in the middle of a thunderstorm).

A landslide or avalanche consists of two distinct areas: the bury zone (in the direct path of the falling debris) and the slide zone (the area the debris spreads our to encompass). Characters in the bury zone always take damage from the avalanche; characters in the slide zone maybe able to get our of the way. Characters in the bury zone take 8d6 points of damage, or half that amount if they make a DC IS Reflex save. They are subsequently buried (see below).

Characters in the slide zone take 3d6 points of damage, or no damage if they make a DC 15 Reflex save, Those who fail their saves are buried.

Buried characters take 1d6 points of nonlethal damage per minute. If a buried character falls unconscious, he or she as make a DC 15 Constitution check or take 1d6 points of lethal damage each minute thereafter until freed or dead.

The typical avalanche has a width of 1d6x100 feet, from edge of the slide zone to the opposite edge. The bury zone in the center of the avalanche is half as wide as the avalanche's full width. To determine the precise location of characters in the path of avalanche, roll 1d6x20; the result is the number of feet from center of the path taken by the bury zone to the center of the party's location. Avalanches of snow and ice advance at a speed 500 feet per round, and rock avalanches travel at a speed of 25 feet per round.

Mountain Travel

High altitude can be extremely fatiguing - or sometime deadly - to creatures that aren't used to it. Cold becomes extreme and the lack of oxygen in the air can wear down even the most hardy of warriors.

Acclimated Characters: Creatures accustomed to high altitude generally fare better than lowlanders. Any creature with an Environment entry that includes mountains is considered native to the area, and acclimated to the high altitude. Characters can acclimate themselves by living at high altitude for a month. Characters who spend more than two months away from the mountains must re-acclimate themselves when they return.

Undead, constructs, and other creatures that do not breathe are immune to altitude effects.

Altitude Zones: In general, mountains present three possible altitude bands: low pass, low peak/high pass, and high peak.

Low Pass (lower than 5,000 feet): Most travel in low mountains takes place in low passes, a zone consisting largely of alpine meadows and forests. Travelers may find the going difficult (which is reflected in the movement modifiers for traveling through mountains), but the altitude itself has no game effect.

Low Peak or High Pass (5,000 to 15,000 feet): Ascending to the highest slopes of low mountains, or most normal travel through high mountains, falls into this category. All non-acclimated creatures labor to breathe in the thin air at this altitude. Characters must succeed on a Fortitude save each hour (DC 15, +1 per previous check) or be fatigued. The fatigue ends when the character descends to an altitude with more air. Acclimated characters do not have to attempt the Fortitude save.

High Peak (mere than 15,000 feet): The highest mountains exceed 20,000 feet in height. At these elevations, creatures are subject to both high altitude fatigue (as described above) and altitude sickness, whether or not they're acclimated to high altitudes.

Altitude sickness represents long-term oxygen deprivation, and it affects mental and physical ability scores. After each 6-hour period a character spends at an altitude of over 15,000 feet, he must succeed on a Fortitude save (DC 15, +1 per previous check) or take 1 point of damage to all ability scores.

Creatures acclimated to high altitude receive a +4 competence bonus on their saving throws to resist high altitude effects and altitude sickness, but eventually even seasoned mountaineers must abandon these dangerous elevations.

Desert Terrain

Desert terrain exists in warm, temperate, and cold climates, but all deserts share one common trait: little rain. The three categories of desert terrain are tundra (cold deserts), rocky desert (often temperate), and sandy desert (often warm). See also Wastes.

Desert Terrain Features
 Desert Category
Undergrowth15% 5%5%
Ice sheet25%--
Light rubble5%30%10%
Dense rubble-30%5%
Sand dunes--50%
Sample Warm Desert Encounter Table (EL 7)
d%EncounterAverage EL
01-071 androsphinx9
08-151 gynosphinx8
16-231d3 lamias8
24-311d3 basilisks7
32-411 criosphinx7
42-495th-level human monk NPC and 5th-level human bard NPC7
50-571 flesh golem7
51-691d3 hieracosphinxes7
70-801 Huge monstrous scorpion (vermin)7
81-871d3 jann (genie)6
89-961d4+2 Large monstrous scorpions (vermin)6
97-1001 mummy5

Tundra differs from the other desert categories in two important ways. Because snow and ice cover much of the landscape, it's easy to find water. And during the height of summer, the permafrost thaws to a depth of a foot or so, turning the landscape into a vast field of mud. The muddy tundra affects movement and skill use as the shallow bogs described in marsh terrain, although there's little standing water. The table above describes terrain elements found in each of the three desert categories. The percentages are intended to guide your map-drawing; don't roll for each square. The terrain elements on this table are mutually exclusive; for instance, a square of tundra may contain either light undergrowth or an ice sheet, but not both.

Light Undergrowth: Consisting of scrubby, hardy bushes and cacti, light undergrowth functions as described for other certain types.

Ice Sheet: The ground is covered with slippery ice. It costs 2 squares of movement to enter a square covered by an ice sheet, and the DC of Balance and Tumble checks there increases by 5. A DC 10 Balance check is required to run or charge across an ice sheet.

Light Rubble: Small rocks are strewn across the ground, making nimble movement more difficult more difficult. The DC of Balance and Tumble checks increases by 2.

Dense Rubble: This terrain feature consists of more and larger stones. It costs 2 squares of movement to enter a square with dense rubble. The DC of Balance and Tumble checks increases by 5, and the DC of Move Silently checks increases by 2.

Sand Dunes: Created by the action of wind on sand, sand dunes function as hills that move, if the wind is strong and content, a sand dune can move several hundred feet in a week's time. Sand dunes can cover hundreds of squares. They always have a gentle slope pointing in the direction of the prevailing wind and steep slope on the leeward side.

Other Desert Terrain Features: Tundra is sometimes bordered by forests, and the occasional tree isn't out of place in the cold wastes. Rocky deserts have towers and mesas consisting of flat ground surrounded on all sides by cliffs and steep slopes (described in Mountain Terrain). Sandy deserts sometimes have quicksand; this functions as described in Marsh Terrain, although desert quicksand is a waterless mixture of fine sand and dust. All desert terrain is crisscrossed with dry streambeds (treat as trenches 5 to 15 feet wide) that fill with water on the rare occasions when rain falls.

Stealth and Detection in the Desert: In general, the maximum distance in desert terrain at which a Spot check for detecting the nearby presence of others can succeed is 6d6x20 feet; beyond this distance, elevation changes and heat distortion in warm deserts makes spotting impossible. The presence of dunes in sandy deserts limits spotting distance to 6d6X10 feet.

The desert imposes neither bonuses nor penalties on listen or Spot checks. The scarcity of undergrowth or other elements that offer concealment or cover makes hiding more difficult.


A sandstorm reduces visibility to 1d100x5 feet and provides a penalty on listen, Search, and Spot checks. A sandstorm deals 1d3 points of nonlethal damage per hour to any creatures caught in the open, and leaves a thin coating of sand in its wake. Driving sand creeps in through all but the most secure seals and seams, to chafe skin and contaminate carried gear.

Plains Terrain

Plains are where most civilizations flourish, so they are often settled. Plains come in three categories: farms, grasslands, and battlefields. Farms are common in settled areas, of course, while grasslands represent untamed plains. The battlefields where large armies clash are temporary places, usually reclaimed by natural vegetation or the farmer's plow. Battlefields represent a third terrain category because adventurers tend to spend a lot of time there, not because they're particularly prevalent.

The table below shows the proportions of terrain elements in the different categories of plains. On a farm, light undergrowth represents most mature grain crops, so farms growing vegetable crops will have less light undergrowth, as will all farms during the time between harvest and a few months after planting.

The terrain elements in the table below are mutually exclusive.

Plains Terrain Features
 Plains Category
Light undergrowth40%20%10%
Heavy undergrowth- 10%-
Light rubble--10%
Berm --5%
Sample Temperate Plains Encounter Table (EL4)
d%EncounterAverage EL
01-031 half-dragon, 4th-level human fighter6
04-081d4+2 worgs6
09-131d3 cockatrices5
14-191d3 locust swarms5
20-265th-level human paladin NPC5
27-351d3 blink dogs4
36-441d3 giant soldier ants4
45-571d4+4 goblins4
58-691d3 wererats (lycanthrope)4
70-781 vampire spawn4
79-861 allip3
87-941 ankheg3
95-1001d3 gnolls3

Undergrowth: Whether they're crops or natural vegetation, the tall grasses of the plains function like light undergrowth in a forest. Particularly thick bushes form patches of heavy undergrowth that dot the landscape in grasslands.

Light Rubble: On the battlefield, light rubble usually represents something that was destroyed: the ruins of a building or the scattered remnants of a stone wall, for example. It functions as described in the desert terrain section above.

Trench: Often dug before a battle to protect soldiers, a trench functions as a low wall, except that it provides no cover against adjacent foes. It costs 2 squares of movement to leave a trench, but it costs nothing extra to enter one. Creatures outside a trench who make a melee attack against a creature inside the trench gain a +1 bonus on melee attacks because they have higher ground. In farm terrain, trenches are generally irrigation ditches.

Berm: A common defensive structure, a berm is a low, earthen wall that slows movement and provides a measure of cover. Put a berm on the map by drawing two adjacent rows of steep slope (described in Hills Terrain, above), with the edges of the berm on the downhill side. Thus, a character crossing a two-square berm will travel uphill for 1 square, then downhill for 1 square. Two-square berms provide cover as low walls for anyone standing behind them, larger berms provide the low wall benefit for anyone standing 1 square downhill from the top of the berm.

Fences: Wooden fences are generally used to contain livestock or impede oncoming soldiers. It costs an extra square of movement to cross a wooden fence. A stone fence provides a measure of cover as well, functioning as low walls. Mounted characters can cross a fence without slowing their movement if they succeed on a DC 15 Ride check. If the check fails, the steed crosses the fence, but the rider falls out of the saddle.

Other Plains Terrain Features: Occasional trees dot the landscape in many plains, although on battlefields they're often felled to provide raw material for siege engines (described in Urban Features). Hedgerows (described in Marsh Terrain) are found in plains as well. Streams, generally 5 to 20 feet wide and 5 to 10 feet deep, are commonplace.

Stealth and Detection in Plains: in plains terrain, the maximum distance at which a Spot check for detecting the nearby presence of others can succeed is 6d6X40 feet, although the specifics of your map may restrict line of sight.

Plains terrain provides no bonuses or penalties on listen and Spot checks. Cover and concealment are not uncommon, so a good place of refuge is often nearby, if not right at hand.

Aquatic Terrain

Aquatic terrain is the least hospitable to most PCs, because they can't breathe there. Characters are as likely to find themselves unwillingly thrust into the water (when it's at the bottom of a pit, for example) as they are to intentionally seek adventure under the waves.

Aquatic terrain doesn't offer the variety that land terrain does. The ocean floor holds many marvels, including undersea analogues of any of the terrain elements described earlier in this section. But if your characters find themselves in the water because they were bull rushed off the deck of a pirate ship, the tall kelp beds hundreds of feet below them don't matter.

Accordingly, these rules simply divide aquatic terrain into two categories: flowing water (such as streams and rivers) and non-flowing water (such as lakes and oceans).

Sample Temperate Aquatic Encounter Table (EL 8)
01-041 juvenile bronze dragon9
05-081 dragon turtle9
09-171 giant squid (animal)9
18-281 giant octopus (animal)8
29-391d4+2 sea cats8
40-561d4+2 Huge sharks (animal)8
57-702d4+4 tritons8
71-831 cachalot whale (animal)7
84-941 water naga7
95-1001d4 merrow (ogre)6

Flowing Water: large, placid rivers move at only a few miles per hour, so they function as still water for most purposes. But some rivers and streams are swifter; anything floating in them moves downstream at a speed of 10 to 40 feet per round. The fastest rapids send swimmers bobbing downstream at 60 to 90 per round. Fast rivers are always at least rough water (Swim 15), and whitewater rapids are stormy water (Swim DC 20).

If a character is in moving water, move her downstream the indicated distance at the end of her turn. A character trying to maintain her position relative to the riverbank can spend some or all of her turn swimming upstream.

Swept Away: Characters swept away by a river moving 60 feet per round or faster must make DC 20 Swim checks every round to avoid going under, if a character gets a check result of 5 or more over the minimum necessary, he arrests his motion by catching a rock, tree limb, or bottom snag - he is no longer being carried along by the flow of the water. Escaping the rapids by reaching the bank requires three DC 20 Swim checks in a row. Characters arrested by a rock, limb, or snag can't escape under their own power unless they strike out into the water and attempt to swim their way clear. Other characters can rescue them as if they were trapped in quicksand (described in Marsh Terrain).

Nonflowing Water: lakes and oceans simply require a swim speed or successful Swim checks to move through (DC 10) calm water, DC 15 in rough water, DC 20 in stormy water). Characters need a way to breathe if they're underwater; failing that, they risk drowning (see Drowning). When underwater, characters can move in any direction as if they were flying with perfect maneuverability.

Stealth and Detection Underwater: How far you can see underwater depends on the water's clarity. As a guideline, creatures can see 4d8x10 feet if the water is clear, and 1d6x10 feet if it's murky. Moving water is always murky, unless it's in a particularly large, slow-moving river.

It's hard to find cover or concealment to hide underwater (except along the seafloor), listen and Move Silently checks function normally underwater.

Invisibility: An invisible creature displaces water and leaves a visible, body-shaped "bubble" where the water was displaced. The creature still has concealment (20% miss chance), but not total concealment (50% miss chance).

Underwater Combat

Land-based creatures can have considerable difficulty when fighting in water. Water affects a creature's Armor Class, attack rolls, damage and movement. In some cases a creature's opponents may get a bonus on attacks. The effects are summarized in the accompanying table. They apply whenever a character is swimming, walking in chest-deep water, or walking along the bottom.

Ranged Attacks Underwater: Thrown weapons are ineffective underwater, even when launched from land. Attacks with other ranged weapons take a -2 penalty on attack rolls for every 5 feet of water they pass through, in addition to the normal penalties for range.

Attacks from Land: Characters swimming, floating, or treading water on the surface, or wading in water at least chest deep, have improved cover (+8 bonus AC, +4 bonus on Reflex saves) from opponents on land. Land-based opponents who have freedom of movement effects ignore this cover when making melee attacks against targets in the water. A completely submerged creature has total cover against opponents an land unless those opponents have freedom of movement effects. Magical effects are unaffected except for those that require attack rolls (which are treated like any other effects) and fire effects.

Fire: Nonmagical fire (including alchemist's fire) does not burn underwater. Spells or spell-like effects with the fire descriptor are ineffective underwater unless the caster makes a Spellcraft check (DC 20 + spell level). If the check succeeds, the spell creates a bubble of steam instead of its usual fiery effect, but otherwise the spell works as described. A supernatural fire effect is ineffective underwater unless its description states otherwise.

The surface of a body of water blocks line of effect for any fire spell. If the caster has made a Spellcraft check to make the fire spell usable underwater, the surface still blocks the spell's line of effect. For example, a fireball cast underwater cannot be targeted at creatures above the surface.

Combat Adjustments Underwater
ConditionSlashing or BludgeoningTailMovementOff Balance?
Freedom of movementnormal/normalnormal/normalnormalNo
Has a swim speed-2/halfnormalnormalNo
Successful Swim check-2/half- 2/halfquarter or halfNo
Firm footing-2/half-2/halfhalfNo
None of the above-2/half- 2/halfnormalYes
1 A creature without a freedom of movement effects or a swim speed makes grapple checks underwater at a -2 penalty, but deals damage normally when grappling.
2 A successful Swim check lets a creature move one-quarter its speed as a move action or one-half its speed as a full-round action.
3 Creatures have firm footing when walking along the bottom, braced against a ship's hull, or the like. A creature can only walk along the bottom, it wears or carries enough gear to weigh itself down - at least 16 pounds for Medium creatures, twice that for each size category larger than Medium, and half that for each size category smaller than Medium.
4 Creatures flailing about in the water (usually because they failed their Swim checks) have a hard time fighting effectively. An off balance creature loses its Dexterity bonus to Armor Class, and opponents gain a +2 bonus on attacks against it.


In many wilderness areas, river floods are a common occurrence. In spring, an enormous snowmelt can engorge the streams and rivers it feeds. Other catastrophic events such as massive rainstorms or the destruction of a dam can create floods as well.

During a flood, rivers become wider, deeper, and swifter. Assume that a river rises by 1d10+10 feet during the spring flood, and its width increases by a factor of 1d4x50%. Fords may disappear for days, bridges may be swept away, and even ferries might not be able to manage the crossing of a flooded river.

A river in flood makes Swim checks one category harder (calm water becomes rough, and rough water becomes stormy). Rivers also become 50% swifter.


Sometimes weather can play an important role in an adventure - rain can wash away tracks, a thunderstorm can force the adventurers to seek shelter, or a gale can delay their ship from sailing.

If your adventure involves spending a lot of time outdoors, create a random table to determine the weather conditions in a particular area. Local conditions have a dramatic effect on weather. High-altitude areas are often much colder than lowlands, for example. The presence of a mountain range can cause an area adjacent to the mountains where little precipitation falls.

Calm: Wind speeds are light (0 to 10 mph).

Cold: Between 0° and 40° Fahrenheit during the day, 10 to 20 degrees colder at night.

Cold Snap: lowers temperature by -10° F.

Downpour: Treat as rain (see Precipitation, below), but conceals as fog. Can create floods (see above). A downpour lasts for 2d4 hours.

Heat Wave: Raises temperature by +10° F.

Hot: Between 85° and 110° Fahrenheit during the day, 10 to 20 degrees colder at night.

Moderate: Between 40° and 60° Fahrenheit during the day, 10 to 20 degrees colder at night.

Powerful Storm (Windstorm/Blizzard/Hurricane/Tornado): Wind speeds are over 50 mph (see Wind Effects). In addition, blizzards are accompanied by heavy snow (1d3 feet), and hurricanes are accompanied by downpours (see above). Windstorms last for 1d6 hours. Blizzards last for 1d3 days. Hurricanes can last for up to a week, but their major impact on characters will come in a 24-to-48-hour period when the center of the storm moves through their area, Tornadoes are very short-lived (1d6x10 minutes), typically forming as part of a thunderstorm system.

Snow and sleet occur only when the temperature is 30° Fahrenheit or below. Most precipitation lasts for 2d4 hours. By contrast, hail lasts for only 1d20 minutes but usually accompanies 1d4 hours of rain.

Storm (Duststorm/Snowstorm/Thunderstorm): Wind speeds are severe (30 to 50 mph) and visibility is cut by three-quarters. Storms last for 2d4-1 hours. See Storms for more details.

Warm: Between 60° and 85° Fahrenheit during the day, 10 to 20 degrees colder at night.

Windy: Wind speeds are moderate to strong (10 to 30 mph); see Wind Effects.

Rain, Snow, Sleet, and Hail

Bad weather frequently slows or halts travel and makes it virtually impossible to navigate from one spot to another. Torrential downpours and blizzards obscure vision as effectively as a dense fog.

Most precipitation is rain, but in cold conditions it can manifest as snow, sleet, or hail. Precipitation of any kind followed by a cold snap in which the temperature dips from above freezing to 30' F or below may produce ice (see Cold Dangers).

Rain: Rain reduces visibility ranges by half, resulting in a -4 penalty on Spot and Search checks. It has the same effect on flames, ranged weapon attacks, and listen checks as severe wind.

Snow: Falling snow has the same effects on visibility, ranged weapon attacks, and skill checks as rain, and it costs 2 squares of movement to enter a snow-covered square. A day of snowfall leaves 1d6 inches of snow on the ground.

Heavy Snow: Heavy snow has the same effects as normal snowfall, but also restricts visibility as fog does (see Fog). A day of heavy snow leaves 1d4 feet of snow on the ground, and it costs 4 squares of movement to enter a square covered with heavy snow. Heavy snow accompanied by strong or severe winds may result in snowdrifts 1d4x5 feet deep, especially in and around objects big enough to deflect the wind - a cabin or a large tent, for instance. There is a 10% chance that a heavy snowfall is accompanied by lightning (see Thunderstorm).

Snow has the same effect on flames as moderate wind.

Sleet: Essentially frozen rain, sleet has the same effect as rain while falling (except that its chance to extinguish protected flames is 75%) and the same effect as snow once on the ground.

Hail: Hail does not reduce visibility, but the sound of falling hail makes listen checks more difficult (-4 penalty). Sometimes (5% chance) hail can become large enough to deal 1 point of lethal damage (per storm) to anything in the open. Once on the ground, hail has the same effect on movement as snow.


The combined effects of precipitation (or dust) and wind that accompany all storms reduce visibility ranges by three quarters, imposing a -8 penalty on Spot, Search, and listen checks. Storms make ranged weapon attacks impossible, except for those using siege weapons, which have a -4 penalty on attack rolls. They automatically extinguish candles, torches, and similar unprotected flames. They cause protected flames, such as those of lanterns, to dance wildly and have a 50% chance to extinguish these lights. See Wind Effects for possible consequences to creatures caught outside without shelter during such a storm. Storms are divided into the following three types:

Duststorm (CR 3): These desert storms differ from other storms in that they have no precipitation. Instead, a duststorm blows fine grains of sand that obscure vision, smother unprotected flames and can even choke protected flames (50% chance). Most dust storms are accompanied by severe winds and leave behind a deposit of 1d6 inches of sand. However, there is a 10% chance for a greater duststorm to be accompanied by windstorm-magnitude winds (see Wind Effects). These greater duststorms deal 1d3 points of nonlethal damage each round to anyone caught out in the open without shelter and also pose a choking hazard (see Drowning - except the a character with a scarf or similar protection across her mouth and nose does nor begin to choke until after a number of rounds equal to 10 x her Constitution score). Greater duststorms leave 2d3+1 feet of fine sand in their wake.

Snowstorm: In addition to the wind and precipitation common to other storms, snowstorms leave 1d6 inches of snow on the ground afterward.

Thunderstorm: In addition to wind and precipitation (usually rain, but sometimes also hail), thunderstorms are accompanied by lightning that can pose a hazard to characters without proper shelter (especially those in metal armor). As a rule of thumb assume one bolt per minute for a 1-hour period at the center a the storm. Each bolt causes electricity damage equal to 1d10 eight-sided dice. One in ten thunderstorms is accompanied by a tornado).

Powerful Storms: Very high winds and torrential precipitation reduce visibility to zero, making Spot, Search, and Listen checks and all ranged weapon attacks impossible. Unprotected flames are automatically extinguished, and protected flames have a 75% chance of being doused. Creatures caught in the area may make a DC 20 Fortitude save or face the effects based on the size the creature (see Wind effects). Powerful storms are divided into the following four types.

Windstorm: While accompanied by little or no precipitation windstorms can cause considerable damage simply through the force of their wind,

Blizzard: The combination of high winds, heavy snow (typical 1d3 feet), and bitter cold (see Cold Dangers) make blizzards deadly for all who are unprepared for them.

Hurricane: In addition to very high winds and heavy rain, hurricanes are accompanied by floods. Most adventuring activity is impossible under such conditions.

Tornado: One in ten thunderstorms is accompanied by a tornado. (see Wind Effects)


Whether in the form of a low-lying cloud or a mist rising from the ground, fog obscures all sight, including darkvision, beyond feet, Creatures 5 feet away have concealment (attacks by or against them have a 20% miss chance).


Wind can create a stinging spray of sand or dust, fan a large fire, heel over a small boar, and blow gases or vapors away. If powerful enough, it can even knock characters down (Wind Effects), interfere with ranged attacks, or impose penalties on some skill checks.

Light Wind: A gentle breeze, having little or no game effect.

Moderate Wind: A steady wind with a 50% chance of extinguishing small, unprotected flames, such as candles.

Strong Wind: Gusts that automatically extinguish unprotected flames (candles, torches, and the like). Such gusts impose a -2 penalty on ranged attack rolls and on listen checks.

Severe Wind: In addition to automatically extinguishing any unprotected flames, winds of this magnitude cause protected flames (such as those of lanterns) to dance wildly and have a 50% chance of extinguishing these lights. Ranged weapon attacks and listen checks are at a -4 penalty This is the velocity of wind produced by a gust of wind spell.

Windstorm: Powerful enough to bring down branches if not trees, windstorms automatically extinguish unprotected and have a 75% chance of blowing our protected flames, such as those of lanterns. Ranged weapon attacks are impossible, and even siege weapons have a -4 penalty on attack rolls, listen checks are at a -8 penalty due to the howling of the wind.

Hurricane-Force Wind: All flames are extinguished. Ranged attacks are impossible (except with siege weapons, which have a -8 penalty on attack rolls), listen checks are impossible: All character can hear is the roaring of the wind. Hurricane-force winds often fell trees.

Tornado (CR 10): All flames are extinguished. All ranged attacks impossible (even with siege weapons), as are listen checks. Instead of being blown away (see Wind Effects), characters in close proximity to a tornado who fail their Fortitude are sucked toward the tornado. Those who come in contact with the actual funnel cloud are picked up and whirled around for 1d10 rounds, taking 6d6 points of damage per round, before being violently expelled (falling damage may apply). While a tornado's rotational speed can be as great as 300 mph, the funnel itself moves forward at an average of 30 mph (roughly 250 feet per round). A tornado uproots trees, destroys buildings, and causes other similar forms of major destruction.

Wind Effects
Wind ForceWind SpeedRanged Attacks
Normal/Siege Weapons
Creature SizeWind Effect on CreaturesFort Save DC
Light0-10 mph-/-AnyNone-
Moderate11-20 mph-/- AnyNone-
Strong21-30 mph-2/-Tiny or smallerKnocked down10
Small or largerNone
Severe31-50 mph-4/-TinyBlown away15
SmallKnocked down
Large or largerNone
Windstorm51-74 mphImpossible/-4Small or smallerBlown away18
MediumKnocked down
Large or HugeChecked
Gargantuan or ColossalNone
Hurricane75-174 mphImpossible/-8Medium or smallerBlown away20
LargeKnocked down
Gargantuan or ColossalNone
Tornado175-300 mphImpossible/impossibleLarge or smallerBlown away30
HugeKnocked down
Gargantuan or ColossalChecked
The siege weapon category includes ballista and catapult attacks as well as boulders tossed by giants.
Flying or airborne creatures are treated as one size category smaller than their actual size, so an airborne Gargantuan dragon is treated as Huge for purposes of wind effects.
Checked: Creatures are unable to move forward against the force of the wind. Flying creatures are blown back 1d6x5 feet.
Knocked Down: Creatures are knocked prone by the force of the wind. Flying creatures are instead blown back 1d6x10 feet.
Blown Away: Creatures on the ground are knocked prone and rolled 1d4x10 feet, taking 1d4 points of nonlethal damage per 10 feet. Flying creatures are blown back 2d6x10 feet and take 2d6 points of nonlethal damage due to battering and buffeting.