Rev, Tithe Extractor

Whenever you attack, target creature gains
deathtouch until end of turn.
Whenever one or more creatures you control
deal combat damage to a player, create a
Treasure token, then look at the top card of that
player's library and exile it face down. You may
cast that card for as long as it remains exiled.
(A Treasure token is an artifact with "{t}, Sacrifice
this artifact: Add one mana of any color.")