Mr. Sinister's Lair

Hideaway 4 (When this land enters the battlefield, look at the top four cards of your library, exile one face down, then put the rest on the bottom in a random order.)

Mr. Sinister's Lair enters the battlefield tapped.

{t}: Add {g}.

{g}, {t}: You may play the exiled card without paying its mana cost if creatures you control have total power 10 or greater.