T'Ka-Boolk'na is a gigantic, intelligent Giant Crab with a shell as hard as stone and great glowing eyes. The Crab-priests claim that it created Crabmen from coral and pebbles, and that it expects its creations to protect each other and work for it. In exchange, it may occasionally aid Crabmen in time of great need, and is in general more likely to refrain from eating its worshippers. Particularly favored Crabmen are said to enter its entourage of Giant Crabs after death.
T'Ka-Boolk'na can be propitiated with nearly any food offering; the Crabman practice of offering drowned Men as a special occasional offering is mere superstition, as T'Ka-Boolk'na could not care less what sort of flesh or fish it eats, so long as it is available with frequency and in abundance. If sufficient food is not made available, T'Ka-Boolk'na will procure it with a total lack of discrimination.
T'Ka-Boolk'na can see with perfect clarity in the blackness of the deep, and can dim the glow of its eyes to stalk prey with surprising delicacy and stealth.
In combat, T'Ka-Boolk'na uses its two great claws. On any natural attack roll of 19 or 20, its attack severs a limb or head of its opponent, as determined by the Referee. Unless hungry, the God prefers to send into battle its Giant Crabs, 5d6 of which attend it at any given time, subsisting on its leavings.
If hard pressed or faced with many opponents, T'Ka-Boolk'na calls forth a horde of tiny crabs, equivalent to a Creeping Doom spell. It may only perform this summoning once per hour, and cannot make melee attacks during the round it does so.
T'Ka-Boolk'na regenerates 4 hp per round, and severed portions of the God will wriggle back to rejoin its main body. The only wounds that cannot so heal are those caused by acid, Disintegration (which causes 5d4 damage rather than its usual effect, Saving Throw notwithstanding, if it overcomes the God's Magic Resistance), and damage done by highly Lawful or Chaotic magic swords. Regeneration continues until T'Ka-Boolk'na has been reduced to 0 or fewer hp and remains so for 3 consecutive rounds, although the God can do nothing but regenerate while so damaged.