Choker (CR 2)

Small Aberration
Alignment: Usually chaotic evil
Initiative: +6 (+2 Dex, +4 Improved Initiative); Senses: darkvision 60 ft.
Languages: Undercommon

AC: 17 (+1 size, +2 Dex, +4 natural), touch 13, flat-footed 15
Hit Dice: 3d8+3 (16 hp)
Fort +2, Ref +5, Will +4
Speed: 20 ft., climb 10 ft.
Space: 5 ft./10 ft.
Base Attack +2; Grapple +5
Attack: tentacle slap +6 melee
Full Attack: 2 tentacles slap +6 melee
Damage: Tentacle slap 1d3+3
Special Attacks/Actions: Improved grab, constrict 1d3+3
Abilities: Str 16, Dex 14, Con 13, Int 4, Wis 13, Cha 7
Special Qualities: quickness
Feats: Improved Initiative; Lightning Reflexes; Stealthy
Skills: Climb +16, Hide +10, and Move Silently +4
Advancement: 4-6 HD (Small); 7-12 HD (Medium-size)
Climate/Terrain: Any underground
Organization: Solitary
Treasure/Possessions: 1/10 coins, 50% goods, 50% items

Source: Monster Manual

Haste (Su): Although not particularly dexterous, a choker is supernaturally quick. It can take an extra partial action each round, as if affected by a haste spell.

Improved Grab (Ex): To use this ability, the choker must hit an opponent of up to Large size with a tentacle attack. If it gets a hold, it can constrict.

Constrict (Ex): A choker deals 1d3+3 points of damage with a successful grapple check against Large or smaller creatures. Because it seizes victims by the neck, a creature in the choker's grasp cannot speak or cast spells with verbal components.

A choker likes to perch near the ceiling, often at intersections, arch ways, wells, or staircases and reach down to attack its prey. A choker attacks creatures of almost any size, but prefers lone prey of at least Small size. If very hungry, it may attack a group, but it waits to grab the last creature in line.

Chokers are sly and greedy. Quick-thinking parties that spot one before it attacks might be able to bribe a choker with food and question it about the area around its lair.