Grafdigger's Cage

Oracle Text

Creature cards in graveyards and libraries can't enter the battlefield.

Players can't cast spells from graveyards or libraries.

Card Rulings

3/14/2017 If a creature card tries to enter the battlefield from a graveyard or library, it stays in its current zone.
3/14/2017 The second ability doesn’t stop players from playing land cards from graveyards or libraries since lands aren’t cast.