The Gaatji (gah’-ti-jee) dwell in the same watery environs as the Fombui, but unlike those strange, peaceful creatures, the Gaatj are fearsome worshippers of chaos. These monsters build crude villages out of rocks and coral, constructing their squat buildings so that they clump together, interconnected and maze-like. A Gaatj appears to be a bizarre sort of squid, but with two “feathered” tentacles and numerous lateral fins projecting from either side of its oblong body. Its bulbous eyes project from the skull on squat stalks. An adult Gaatj measures between 5-7 feet long from skull to tail with tentacles a foot or so shorter than overall body length.
A Gaatj attacks with its tentacles. After a tentacle hits, it automatically does 1d8 points of damage per round instead of the initial 1d4. Also, there is a 20% chance that the tentacle pinions one of the victim’s limbs (roll randomly for left/right arms and legs to see which is immobilized). Gaatji cast both Magic-User spells (3/1) and Cleric spells (2). They are also vulnerable to electricity-based attacks, suffering a -2 on their saving throws and taking +25% damage from such effects.
Swords & Wizardry
Hit Dice: 3+3
Armor Class: 6 
Attacks: 2 tentacles (1d4) (see below)
Saving Throw: 14
Special: Constriction, spells, vulnerable to electricity
Move: 3/12 (swimming)
Challenge Level/XP: 6/400