Coven Counters

Wall of Mourning

Defender
When this creature enters, exile a card from the top of your library face down for each opponent you have.
Coven — At the beginning of your end step, if you control three or more creatures with different powers, put a card exiled with this creature into its owner's hand.

Defender
When Wall of Mourning enters the battlefield, exile a card from the top of your library face down for each opponent you have.
Coven — At the beginning of your end step, if you control three or more creatures with different powers, put a card exiled with Wall of Mourning into its owner's hand.