The Cube

When The Cube enters the battlefield put {x} Portal Counters on The Cube.
When you play a creature from the
command zone you may play it for free then
remove a Portal Counter from the cube,
if the creature is legendary remove 2.
If a card would enter a different zone you may
remove 1 Portal Counter from The Cube and
put that card into your command zone.
If The Cube has no Portal Counters on it,
shuffle it into your deck.