Wraithworm

The wraithworm's a magical snake commonly found in arid regions such as deserts, rocky wastes, or barren badlands. It's especially common in the layer of Minethys on Carceri, and the white wastes of Pelion on Arborea. Like many other mundane creatures, long exposure to the strange energies and magics of the planes've given the wraithworm powerful magical talents.

A wraithworm's a large, powerful serpent with coal-black scales and bright green, glowing eyes. A diamond pattern of dark purple bands runs down the center of the serpent's back. Its head is nearly the size of a human's, and its fangs are a good three inches in length. The wraithworm's spine features sharp, bony spikes that actually jut through the scales of its back, but the creature doesn't use these offensively - they're simply a deterrent to anything that might try to eat the reptile.

Combat: Wraithworms are slow-moving and lethargic, but they don't rely on speed to catch their prey; they rely on stealth. When they close within striking range, they can attack with blinding speed. A wraithworm's bite inflicts 1d8 points of damage, drains 1d2 levels from the victim, and poisons him with a slow-working but powerful venom that inflicts 3-12 points of damage every hour for the next 1d6 hours. During this time the intense, icy cold of the venom at work inflicts a -4 penalty to the victim's attack rolls, Armor Class, and saving throws. The victim is allowed two saving throws when bitten: the first save, versus spell, negates the level drain if successful; the second, versus poison with a -2 penalty, negates the effects of the wraithworm's poison.

The wraithworm has the power to assume wraithform, as the spell, for up to 1 turn per hour. In this state, the serpent can be damaged only by +1 or better weapons and can slip through the tiniest openings or narrow cracks. The wraithworm uses this power to creep up on potential meals or to escape from dangerous antagonists.

Any creature of 4 HD or fewer meeting the wraithworm's gaze must survive a saving throw versus spell or become paralyzed and unable to move for 2d4 rounds. The snake must be in its tangible form to use this power, and it's effective only within 15 feet. The wraithworm can take no other action when it attempts to use its gaze this way.

Wraithworms suffer only half damage from cold or negative energy attacks. Oddly enough, a priest can hold a wraithworm motionless for 1 to 3 rounds by succeeding a turn attempt against a spectre.

Habitat/Society: Wraithworms are solitarv creatures. They're very territorial and don't tolerate other predators of any kind in their hunting grounds. The wraithworm doesn't have a burrow or lair; it spends its entire life roving its territory, searching for prey.

Ecology: No one's ever come up with a good explanation for why wraithworms're able to do the things they do. Obviously, the creature mimics several powers commonly associated with the undead - its bite drains levels, it's partially immune to cold damage, and it can assume an intangible state. Even the bitter-cold pain caused by the creature's venom at work suggests supernatural elements. The most widely accepted answer is that some evil power or greater fiend made the wraithworm the way it is for its own purposes or amusement, or that the species simply spent too much time in the wrong places.

Although wraithworms possess several unnatural characteristics, they're natural creatures and fit into the local ecosystems without destroying them.

They commonly hunt small animals and birds, and it's fairly rare for wraithworms to attack humans out of hunger. Normally, wraithworms avoid humans and strike only when some poor sod happens to blunder too close for the snake's comfort.