Snake, Huge Sea (CR 3)

Huge Animal
Alignment: Always neutral
Initiative: +6 (+2 Dex, +4 Improved Initiative); Senses: scent, Listen +7, and Spot +7

AC: 15 (-2 size, +2 Dex, +5 natural), touch 10, flat-footed 15
Hit Dice: 6d8+6 (33 hp)
Fort +6, Ref +7, Will +3
Speed: 10 ft., swim 30 ft.
Space: 15 ft./10 ft.
Base Attack +4; Grapple +15
Attack: Bite +5 melee
Full Attack: Bite +5 melee
Damage: Bite 1d6+4 and poison
Special Attacks/Actions: Poison
Abilities: Str 16, Dex 15, Con 13, Int 1, Wis 12, Cha 2
Special Qualities: hold breath
Feats: Improved Initiative; Run; Weapon Focus (bite)
Skills: +10, Balance, Climb +11, Hide +3, Listen +7, Spot +7, and Swim +11
Advancement: 7-18 HD (Huge)
Climate/Terrain: Warm aquatic
Organization: Solitary
Treasure/Possessions: None

Source: Stormwrack

Poison (Ex) Bite, Fortitude save (DC 15); initial and secondary damage 1d6 temporary Constitution. A sea snake's poison is extraordinarily virulent. It has a +2 racial bonus on the poisons save DC.

Hold Breath (Ex): A sea snake can hold its breath for a number of rounds equal to 6 x its Constitution score before it risks drowning. For a typical sea snake, this is 66 rounds, or over 6 minutes.

Skills: A sea snake 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.

Improved Initiative: +4 on Initiative checks