Snake, Large Viper (CR 2)

Large Animal
Alignment: Always neutral
Initiative: +7 (+3 Dex, +4 Improved Initiative); Senses: scent, Listen +5, and Spot +6


AC: 15 (-1 size, +3 Dex, +3 natural), touch 12, flat-footed 12
Hit Dice: 3d8 (13 hp)
Fort +3, Ref +6, Will +2
Speed: 20 ft., climb 20 ft., swim 20 ft.
Space: 10 ft./5 ft.
Base Attack +2; Grapple +6
Attack: Bite +4 melee
Full Attack: Bite +4 melee
Damage: Bite 1d4 and poison
Special Attacks: Poison
Abilities: Str 10, Dex 17, Con 11, Int 1, Wis 12, Cha 2
Special Qualities:
Feats: Improved Initiative; Weapon Focus (bite)
Skills: +11, Balance, Climb +11, Hide +8, Listen +5, Spot +6, and Swim +8
Advancement: -
Climate/Terrain: Warm forest
Organization: Solitary
Treasure/Possessions: None

Source: Monster Manual

These creatures rely on their venomous bites to kill prey and defend themselves.

Combat

Poison (Ex): Bite, Fortitude save (DC 11); initial and secondary damage 1d6 temporary Constitution.

Improved Initiative: +4 on Initiative checks