Domrath, the Sixth Titan

+3: Search your library for a Legendary Eldrazi creature card, reveal it, and put it into your hand. Then shuffle your library.
-7: Exile all non-Eldrazi creatures. Put a +1/+1 counter on each Eldrazi. Put 2 loyalty counters on each planeswalker.
-15: If you control 4 or more Legendary Eldrazi creatures, you may sacrifice all other permanents you control. If you do, you win the game.