Leviathan Of The Rift

Ward: Exile two permanents you control.
Whenever an opponent casts a spell, that player exiles
the top card of their library. Once each turn, you may cast a face-up exiled card that an opponent owns in exile without paying its mana cost. Whenever this creature
becomes the target of a spell an opponent controls,
target opponent exiles cards from their library until
they exile a nonland card with converted mana cost 8
or greater.