The Ruinous Powers - 139★ R 40K Foil

At the beginning of your upkeep, choose an opponent at random. Exile the top card of that player's library. Until end of turn, you may play that card and you may spend mana as though it were mana of any color to cast it. When you cast a spell this way, its owner loses life equal to its mana value.

rare
Enchantment
From the Magic: The Gathering set Warhammer 40,000 Commander.