Shocker Lizard (CR 2)

Small Magical Beast
Alignment: Always neutral
Initiative: +2 (Dex); Senses: darkvision 60 ft., electricity sense, low-light vision, Listen +4, and Spot +4

AC: 16 (+1 size, +2 Dex, +3 natural), touch 13, flat-footed 14
Hit Dice: 2d10+2 (13 hp)
Fort +4, Ref +5, Will +1
Speed: 40 ft., climb 20 ft., swim 20 ft.
Space: 5 ft./5 ft.
Base Attack +2; Grapple -2
Attack: Bite +3 melee
Full Attack: Bite +3 melee
Damage: Bite 1d4
Special Attacks/Actions: Stunning shock, lethal shock
Abilities: Str 10, Dex 15, Con 13, Int 5, Wis 12, Cha 6
Special Qualities: electricity immunity
Feats: Improved Initiative
Skills: Climb +11, Hide +11, Jump +7, Listen +4, and Spot +4
Advancement: 3-4 HD (Medium-size); 5-6 HD (Large)
Climate/Terrain: Warm marsh
Organization: Solitary, pair, clutch (3-5), or colony (6-11)
Treasure/Possessions: 1/10 coins; 50% goods; 50% items

Source: Monster Manual

Stunning Shock (Su): Once per round, a shocker lizard can deliver an electrical shock to a single opponent within 5 feet. This attack deals 2d8 points of subdual damage to living opponents (Reflex half DC 12).

Lethal Shock (Su): Whenever two or more shocker lizards are within 25 feet of each other, they can work together to create a lethal shock. This effect has a radius of 25 feet, centered on any one contributing lizard. The shock deals 2d8 points of damage for each lizard contributing to it (Reflex half DC 10 + number of lizards contributing).

Electricity Sense (Ex): Shocker lizards automatically detect any electrical discharges within 100 feet.

Skills: Stocker lizards receive a +4 racial bonus to Hide checks due to their coloration.

Unless it is very hungry, a shocker lizard dislikes fighting creatures larger than itself and usually tries to warn off intruders by emitting a series of rapid clicks. The sound is actually a low-power electrical discharge, and living creatures within to feet can feel the current tickling their skins and scalps. If the warning fails, the lizard raises its horns and tail to administer stunning shocks.

A shocker lizard relies on its electrical abilities in combat. A lizard tends to bite only after its shock has rendered an opponent unconscious or when the shock seems to have no effect at all. Lone lizards flee once they deliver their shocks, but if others are nearby, they all home in on their comrade's discharges and administer deadly shocks to the foe.