Caverns of Despair

No more than two creatures can attack each combat.
No more than two creatures can block each combat.

Nether Void

Whenever a player casts a spell, counter it unless that player pays .

Darkness

Prevent all combat damage that would be dealt this turn.

Invoke Prejudice

Whenever an opponent casts a creature spell that doesn’t share a color with a creature you control, counter that spell unless that player pays , where X is its converted mana cost.