Chang, Escapee

Trample
Whenever Chang, Escapee deals combat damage
to a player, you may reveal the top X cards of
your library, where X is half its power, rounded
down. You may pay {g}, {b}{b} or both. If you paid
{g}, put a land from among them to the battle-
field under your control. If you paid {b}{b}, put a
Rogue from among them to the battlefield tapped
under your control. Put the rest into your
graveyard.