Duo-Dimension

A duo-dimension spell causes the caster to have only two dimensions, height and width, with no depth. They are thus invisible when turned sideways. This invisibility can be detected only by means of a true seeing spell or similar methods. In addition, the duodimensional wizard can pass through the thinnest of spaces as long as these have the proper height--going through the space between a door and its frame is a simple matter. The caster can perform all actions normally. They can turn and become invisible, move in this state, and appear again next round and cast a spell, disappearing on the following round.

Note that when turned, the caster cannot be affected by any form of attack, but when visible, they are subject to double the amount of damage normal for an attack form; for example, a dagger thrust would inflict 2d4 points of damage if it struck a duodimensional caster. Furthermore, the caster has a portion of their existence in the Astral Plane when the spell is in effect, and they are subject to possible notice by creatures there. If noticed, it is 25% probable that the caster is pulled entirely into the Astral Plane by any attack from an astral creature. Such an attack (and any subsequent attack received on the Astral Plane) inflicts normal damage.