Faceless Devourer

Oracle Text

Shadow (This creature can block or be blocked by only creatures with shadow.)

When Faceless Devourer enters the battlefield, exile another target creature with shadow.

When Faceless Devourer leaves the battlefield, return the exiled card to the battlefield under its owner's control.

Card Rulings

9/25/2006 Three Faceless Devourers cast in succession with no other creatures with shadow on the battlefield will result in an infinite loop and the game will be a draw, unless a player somehow interrupts the loop.