Sink Worm

Imagine a pale maggot 50 feet or longer, with a gaping mouth lined in sword-like teeth. Below sand or silt it leaves a sunken furrow on the surface, an obvious warning that seldom saves anyone it has chosen to hunt.

The worm creeps in until it is nearly beneath its prey, then erupts and tries to gulp it down. Its bite deals 2d12 points, and an attack roll 4 or more above what it needs swallows the victim whole, if the target fits through a mouth about seven feet wide.

Partly thanks to its phasing, the worm is nearly silent, and its keen senses give it +1 on surprise rolls. Opponents roll normally; success means spotting the sunken trail 10-60 (1d6x10) yards off on sand or 20-120 (2d6x10) yards off in silt. It feels footsteps on sand within 120 yards and waders in silt within 90, and running is especially easy for it to detect.

After swallowing, it dives and chews for an automatic 2d12 points each round, coming back for more if prey remains. A swallowed victim can fight only with a small weapon already in hand, at -1 to attack and damage, worsening by 1 each round. Two rounds past zero hit points, nothing recoverable is left but small pieces.

Phasing carries it through rock outcrops up to 90 feet at a time, unless it would end up inside solid stone. It never phases above ground, where it is slow, but a hungry worm may phase ahead of a fleeing elf or other runner. Hurt, it escapes downward, taking two rounds in sand or one in silt, and it cannot phase with prey in its mouth; past half its hit points it may drop its meal to flee.

Worms meet only to mate, every three years, burying eggs at least 10 feet down where they are hard to find. Hatchlings are abandoned and mostly eat each other, so only a few strong ones burrow off. Needing a man-sized meal or more every day, a worm swallows almost anything it meets.

The worm draws sand and silt right through its body, straining the air between grains across its gills to breathe underground; pulling out that air is what makes the surface sag behind it. Sages covet those gills, so an egg would sell for any price, if anyone could find one.