Gravbeast (CR 6)

Large Magical Beast
Alignment: Usually lawful evil
Initiative: +3 (Dex); Senses: darkvision 60 ft., low-light vision, scent, Listen +5, and Spot +5

AC: 19 (-1 size, +3 Dex, +7 natural), touch 12, flat-footed 16
Hit Dice: 6d10+24 (57 hp); DR: 3/-
Fort +9, Ref +8, Will +5
Speed: 40 ft., climb 40 ft.
Space: 10 ft./5 ft.
Base Attack +6; Grapple +19
Attack: Bite +10 melee
Full Attack: Bite +10 and 4 claws +8 melee
Damage: Bite 1d8+5, claws 1d6+2
Special Attacks/Actions: Knockdown, powerful pounce, reverse gravity
Abilities: Str 20, Dex 17, Con 18, Int 7, Wis 16, Cha 10
Special Qualities: gravatic stability, gravatic turbulence, personal gravity
Feats: Dodge; Mobility; Multiattack; Track (B)
Skills: Balance +7, Climb +13, Hide +6*, Jump +17, Listen +5, Move Silently +9, Spot +5, and Survival +7
Advancement: 7-9 HD (Large); 10-18 HD (Huge)
Climate/Terrain: Temperate forest, hill, or mountains
Organization: Solitary, pair, or pride (6-10)
Treasure/Possessions: 1/10 coins; 50% goods; 50% items

Source: Web

Knockdown (Su): When a gravbeast pounces and hits with one or more claw attacks, the force of the blow might literally knock the opponent to the ground, thanks to the gravbeast's ability to increase its own mass (see Powerful Pounce, below). The gravbeast can attempt a knockdown as a free action without making a touch attack or provoking an attack of opportunity. The knockdown is resolved as though it were a trip attack made by a Huge creature (+8 size bonus; +13 bonus on trip attempts for the creature as presented here). If the attempt fails, the opponent cannot react to trip the gravbeast.

Powerful Pounce (Su): A gravbeast can pounce on prey like a great cat. Unlike a mere animal, however, it can literally increase its mass when leaps on a foe. When a gravbeast charges, it makes six claw attacks and deals double damage on each hit. Thus, each claw deals 2d6+4 points of damage. The gravbeast cannot bite when using this ability.

If supernatural effects are suppressed in the locale where a gravbeast charges, the creature still can make a pounce attack as an extraordinary ability. In that case, it makes six claw attacks, each of which deals 1d6+2 points of damage.

Reverse Gravity (Su): A gravbeast can literally reverse the gravity in an area of its choice. This ability works like the reverse gravity spell, except that the range is 60 feet, the duration is 6 rounds, and the area affected is a cylinder 20 feet in diameter and 40 feet high. The Reflex save DC (when applicable) is 17, and this save DC is Charisma-based.

A gravbeast usually uses this power to break up groups of foes, aiming the effect so that enemies it does not want to fight are in the area of reversed gravity, then attacking any foes left behind. Once the gravbeast activates this ability, it cannot use it again for 2d4+2 rounds.

Gravatic Stability (Su): At will, a gravbeast can instantly alter its mass so that it weighs anywhere from its usual 800 pounds to four times that amount. Using this ability does not require an action, and the gravbeast can alter its mass even when caught flat-footed or during another creature's turn. In any situation in which increased size would help the gravbeast (such as a bull rush, grapple, trip, or overrun), treat it as a Huge creature (+8 size bonus, already included in the grapple modifier given above). If this ability is suppressed, the gravbeast presented here has a grapple bonus of +15.

Gravatic Turbulence (Su): A gravbeast can surround itself with an aura of varying gravity that can foil ranged attacks by deflecting the projectile or thrown weapon. While this power is active, any ranged attack other than a ray has a 50% miss chance.

Once activated, this effect lasts for 6 rounds and cannot be activated again for 2d4+2 rounds. A gravbeast typically uses this power to protect itself from ranged attacks that foes caught in its reverse gravity power may launch against it.

Personal Gravity (Su): At will, a gravbeast can instantly reverse the direction of gravity's pull in relation to itself. Using this ability does not require an action, and the gravbeast can reverse its own gravity even when caught flat-footed or during another creature's turn. If this effect is suppressed, the gravbeast loses its climb speed and its racial bonus on Climb and Jump checks. While it is active, the gravbeast automatically succeeds on Climb checks, takes no damage from falls, and can use levitate (as the spell, caster level 6th) at will.

Skills: A gravbeast receives a +8 racial bonus on Climb and Jump checks, thanks to its personal gravity ability. It also has a +4 racial bonus on Balance, Hide, Move Silently, and Survival checks. In areas of tall grass or heavy undergrowth, its racial bonus on Hide checks increases to +8.

Despite its bloodlust, a gravbeast is cunning enough to wait for a favorable moment to attack. When faced with particularly large or powerful prey, it often hangs back and tracks its victim for a while, waiting until its prey drops its guard to pounce. In battle, the gravbeast usually rears up on its hindmost legs so that it can claw with its other four feet while biting.