Nifern (CR 2)

Medium Animal
Alignment: Always neutral
Initiative: +2 (Dex); Senses: blindsight 60 ft., low-light vision, Listen +3, and Spot +4

AC: 16 (+2 Dex, +4 natural), touch 12, flat-footed 14
Hit Dice: 2d8+4 (10 hp)
Fort +5, Ref +5, Will +2
Speed: 40 ft.
Space: 5 ft./5 ft.
Base Attack +1; Grapple +4
Attack: Claw +4 melee
Full Attack: 2 claws +4 melee and bite +2 melee and sting +2 melee
Damage: Claw 1d6+3, bite 1d8+1, sting 1d4+1 plus poison
Special Attacks/Actions: Poison
Abilities: Str 16, Dex 14, Con 15, Int 2, Wis 14, Cha 9
Special Qualities: hold breath
Feats: Multiattack; Track
Skills: Listen +3, Spot +4, and Survival +4 (+9 when tracking*)
Advancement: 3-4 HD (Medium); 5-6 HD (Large)
Climate/Terrain: Underground
Organization: Solitary, pair, group (3-5), or pack (6-12)
Treasure/Possessions: None

Source: Serpent Kingdoms

Poison (Ex): Sting, Fortitude DC 13, initial damage paralysis for 1d10 rounds, secondary damage 1d4 Str.

Hold Breath (Ex): A nifern can hold its breath for a number of rounds equal to four times its Constitution score before it risks drowning.

Skills: *Because of its keen sense of smell and natural instinct for tracking, a nifern receives a +5 racial bonus on Survival checks made to track.

Niferns prefer to attack their prey in numbers, but their tactics are fairly straightforward. They rush head-on into battle and sting to immobilize their prey. Creatures that prove resistant to the poison are attacked with vicious claws and powerful jaws.