FREQUENCY: Very rare
FREQUENCY: Very rare ([Dungeon Level III])
 

NO. APPEARING: 1
ARMOR CLASS: 3
MOVE: 6"
HIT DICE: 3
% IN LAIR: Nil
TREASURE TYPE: Nil
NO. OF ATTACKS: 1
DAMAGE/ATTACK: 1-4
SPECIAL ATTACKS: Suffocation
SPECIAL DEFENSES: Nil
MAGIC RESISTANCE: Standard
INTELLIGENCE: Average
ALIGNMENT: Chaotic evil
SIZE: See below
LEVEL/X.P. VALUE: III | 105 + 4

This greatly feared undead creature is a form of wraith, but is unusual
as a member of the undead class in that it in no way resembles a
human. It appears as a near-transparent rectangle with varying dimensions
- 11' to 16 broad, 7' to 12' long and '/" thick. It movesalong
ceilings and attacks by dropping on a potential victim; if it hits the
intended target, it envelops him, causing suffocation for: 1-4 hit
points of damage each round subsequent to the initial attack (no
damage wen if the initial attack succeeds). A victim enveloped by a
sheet phantom cannot move, and any damage inflicted on the sheet
phantom while it is enveloping a captive will also accrue to that
victim. Only one man-sized victim may be enveloped at a time, since
the creature wraps i t s whole form around the victim in a tight cylinder,
and he cannot fight back unless the weapon he uses is short (e.g. a
dagger) and was actually in his hand when the creature fell on him.

If the victim of a sheet phantom's enveloping dies from suffocation
(or as a result of damage inflicted, unwittingly, by his comrades),
the sheet phantom merges with his body and the whole becomes a
sheet ghoul (see Sheet Ghoul above).

There are sufficient similarities between this creature and the lurker
above (see ADVANCED DUNGEONS & DRAGONS MONSTER
MANUAL) to lend credence to the speculation that the one is some
kind of undead form of the other.

These creatures are vulnerable to all attack forms except sleep, charm
and other similar spells and are treated as wraiths on the cleric/undead
matrix.
 

by David Wormell