Purple Worm

A massive worm as tall as a castle keep. Has a rotating maw and is covered in purple chitin.

AC 18, HP 57, ATK 2 bite +9 (2d12 + swallow) and 1 sting +9 (1d10 + poison), MV double near (burrow), S 5, D 1, C 3, I -3, W 1, Ch -3, AL N, LV 12

Poison. DC 15 CON or go to 0 HP.

Swallow. On a natural attack roll of 18-20, target is swallowed. Total darkness inside and 2d10 damage per round. Worm regurgitates all swallowed if dealt at least 20 damage in one round to the inside of its gullet.