Chaosweaver Goblin

When Chaosweaver Goblin enters the
battlefield, shuffle your library, then reveal
cards from the top of your library until you
reveal a nonland card with converted mana
cost 3 or less. You may cast that card without
paying its mana cost. Put the revealed cards
on the bottom of your library in a random order.
"Embracing chaos, the weaver of mayhem pulls
threads of chance, crafting chaos from
the unknown."