A Trapper is an amorphous ambush predator which lies in wait of prey in dark underground places such as caves or dungeons; one literally lies flat and pretends to be the floor. They are able to alter their surface coloration and texture to resemble virtually any kind of natural or cut stone, allowing one to fool onlookers and thus gain surprise on 1-5 on 1d6. Common ploys for a trapper are to form part of its body into a “hump” or other protrusion that might be mistaken for a chest, or to present the appearance of a hole or displaced stone that might cover either a treasure or the entrance to some small creature’s lair; any of these methods might be used to lure intelligent creatures onto the trapper.

A trapper can cover an area equal to 40 square feet per hit die; thus, a 10 hit die trapper can cover 400 square feet, or up to a 20- by 20-foot room.

It is when potential victims are standing on its surface that the trapper attacks, rolling itself up around them and crushing them. A 9 HD trapper can entrap at most 2 normal-sized characters (or twice that many small characters); a 10 HD one can entrap 3 such characters, an 11 HD one can entrap 4, and a 12 HD one can entrap up to 5. At the GM’s option, characters near the edge of the creature’s body at the time of attack may be allowed save vs. Death Ray to avoid entrapment, but those at the center are automatically captured.

Victims wearing no armor suffer 3d6 points of damage each round; those in leather, 2d6, and those in metal just 1d6. Entrapped characters are held so firmly that they cannot use weapons, nor cast spells of any kind, though at the referee’s option certain magic items may be usable.

Trappers have a particular resistance to both heat and cold, and suffer only half damage from such attack forms. Entrapped victims are subject to half damage from any area effect spell (such as fireball) which might affect the monster.