Glass Cage

Flash, Indestructible
Glass Cage may trap X number of spells. They
are exiled until Glass Cage leaves the battlefield.
For each creature trapped by Glass Cage, you
lose 1 life. If your life is equal to 10 or less while Glass Cage is on the field, you lose the game.
"Pray that these cages are never opened, for each holds a different kind of Nightmare."