It That Collects

Protection from instant, Wastewalk, Devoid
Cannot be exiled.
When It That Collects enter the battlefield,
choose an opponent. He or she reavels his or her
hand. Exile two of those cards until It That
Collects leaves the battlefield. You may play lands
and cast spells from among the exiled cards as
long as they remain exiled. If you cast a spell
this way, you may spend mana as though it were
mana of any color to cast it.