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.
However, there's a rare variant called the Candy Cane. If it's attack connects, it heals you like the love puppy and teleports you to the closest treasure box not behind a door. They'll be found in mainly undead levels including Candlestick Keep and Firestorm Citadel. Warpcanes and Candy Canes may be found inside Monster Cages.
Example of teleport and concept art coming soon.
It adds a bit of oddity to fights. These should be rare and might just teleport players X meters away and stuns them. Back to a party button would be reliable, but very annoying. They should also disappear once connecting an attack, so that players want to take them out without being hit. They shouldn't be immune to shadow damage - only Vanaduke's final phrase should do that.