Army from Exile

For each charge counter on Army from Exile, each player may return a creature or planeswalker he or she owns from exile to the battlefield.
"They appeared to find form from thin air. A terrifying force of our enemy's undead accompanied
by those thought to be lost. The only solace I find is
in the company of our own fallen and exiled manifesting beside me."
-The Book of The Bizarre Battle.