Ixmathies, Thought Scavenger

Whenever a card is put into an opponent's graveyard from anywhere, exile it. Until end of turn, you may cast that card and spend mana as though it were mana of any color to do so. At the beginning of the next end step, if you didn't cast that card, return it to it's owners graveyard.
You may cast cards you don't own as though they had flash.
"Your mind is a haven only I can access."