Do you know the wallmasters from Zelda? You know, those disembodied hands that warp you back to the dungeon entrance? I've got an idea of a similar enemy.
The Warpcane!
It looks like a floating spiked cane, which slowly flies around at knights. If it gets in reach, it will swing itself at a target.. If the attack connects, the knight is sent back to the last party button pushed (or elevator descended from). If the attack connects to an enemy, it teleports them to a random knight. It is from the Undead family and curiously, is immune to shadow damage.