Deathcoils (CR 7)

Huge Magical Beast
Alignment: Always chaotic evil
Initiative: +3 (Dex); Senses: darkvision 60 ft., low-light vision, scent, Listen +12, and Spot +12

AC: 15 (-2 size, +3 Dex, +4 natural), touch 11, flat-footed 12
Hit Dice: 11d10+14 (74 hp)
Fort +8, Ref +10, Will +4
Speed: 20 ft., climb 20 ft., swim 20 ft.
Space: 15 ft./10 ft.
Base Attack +11; Grapple +26
Attack: Bite +16 melee
Full Attack: Bite +16 melee
Damage: Bite 1d8+10
Special Attacks/Actions: Constrict 1d8+10, improved grab, poison breath
Abilities: Str 25, Dex 17, Con 13, Int 10, Wis 12, Cha 2
Special Qualities:
Feats: Alertness; Endurance; Skill Focus (Hide); Toughness
Skills: Balance +17, Climb +17, Hide +10, Listen +12, Spot +12, and Swim +17
Advancement: 12-22 HD (Huge); 23-33 (Gargantuan)
Climate/Terrain: Temperate forests
Organization: Solitary
Treasure/Possessions: Double standard

Source: Serpent Kingdoms

Constrict (Ex): On a successful grapple check, a deathcoils deals 1d8+10 points of damage.

Improved Grab (Ex): To use this ability, a deathcoils must hit an opponent up to one size category larger than itself with its bite attack. It can then attempt to start a grapple as a free action without provoking an attack of opportunity. If it wins the grapple check, it establishes a hold and can constrict. A deathcoils often drags grabbed prey underwater to drown.

Poison Breath (Ex): Twice per day, a deathcoils can breathe a 60-foot cone of poisonous gas (inhaled, Fortitude DC 16, initial damage sleep for 2d4 hours or until damage is taken, secondary damage 1d6 Con).

Skills: A deathcoils gains a +4 racial bonus on Hide, Listen, and Spot checks and a +8 racial bonus on Balance and Climb checks. A deathcoils can always choose to take 10 on a Climb check, even if rushed or threatened.

A deathcoils can use either its Strength or its Dexterity modifier for Climb checks, whichever is higher.

A deathcoils has a +8 racial bonus on any Swim check to perform some special action or avoid a hazard. It can always choose to take 10 on a Swim check, even if distracted or endangered. It can use the run action while swimming, provided it swims in a straight line.

Deathcoils are aggressive, relentless hunters. Those that live near water often drag their prey underwater to drown it. They usually save their breath weapons for defense against numerous foes, or to slay formidable opponents.

Deathcoils have the intelligence to plan ambushes, and they often collect treasure from victims and scatter it near a cave or a good ambush area to lure prey off a trail. They have also been known to drive animals into ravines and over precipices, then leave their broken bodies for later feasting while they hunt other creatures.