Undead Lake Monster

This rare horror is an enormous, ancient undead water serpent with gray-green hide and a vast mouth full of needle teeth. Its scales have the rank smell and torn look of a zombie's skin, with pale bones showing through the gaps. Swimming at the surface, it appears as a head trailed by a line of rounded humps.

The monster never leaves its lake but attacks anything that wanders near the shore. Its trick is to surface briefly in the middle of the water, dive, and reappear moments later within reach of whoever came closer to look. For all its decay it is very flexible, coiling and twisting with speed, and it can strike like a snake up to 50 feet onto shore or 60 feet above the surface.

Its bite deals 3d8 damage. If a single bite does 8 or more points, its jaws clamp on and it hauls the victim down to its lair. The captive can escape only with a successful Strength check, but may keep trying every round until drowning.

Three times per day it can breathe a cloud of sickly yellow poison 40 feet long and 20 feet wide and high, which acts as the 5th-level wizard spell cloudkill. The vapor drifts with the wind and settles into low spots for four rounds before it disperses. If a fight goes badly, the monster can also produce fear, as the 4th-level wizard spell, three times per day, affecting all within 100 feet who fail a save vs. spell.

It is turned as a 10 HD creature, shares the usual undead immunity to magic that affects bodily functions, and can be hit only by weapons of +1 or better.

Each is believed unique, but some suspect more than one such 'serpent of the depths' lurks in a world, and witnesses claim to have seen two sets of humps on one lake at once. Other sages propose that it guards a brood of young serpents like a protective mother, though how an undead thing could bear offspring is a mystery.

Its lair is said to be heaped with treasure from its drowned victims. Because the lakes it haunts are always hundreds of feet deep, recovering any of it is unlikely, and arms or armor not protected by magic would be rusted to ruin anyway.

As an undead creature the monster has no natural lifespan. Its carcass yields little of use. The hide is tough enough for leather armor or a shield, but its stench forces the wearer to save vs. poison every hour or be nauseated, taking -1 to attack rolls.