The Shroud/Prismatic Wall

The Prismatic wall is a constantly moving vertical, opaque wall—a shimmering, multicolored plane of light that will instantly kill you if your allow it to touch you.

Currently the only one in the game is found in The Shroud, in Phase 3. There is no way to survive it except by running away, escaping to the center area of Phase 3, or using the cleric capstone - Divine Intervention.

The wall moves clockwise through the maze. Be careful around the corners as it creates a new "self" that forms at right angles to move down each section.

How to defeat the wall:
 * Either complete all the puzzles, then fill the water fountains. or
 * Skip the puzzles and fill the waters without completing them. Doing it this way may be faster in some groups, but you will lose a treasure chest in the process, so it's not recommended.

A Prismatic Wall As Seen By A WotC Artist:

http://i44.tinypic.com/2nvxbhk.jpg