Fear of Purity

Destroy all nonblack permanents. Then,
starting with you each player may search their
library for a black card. If that card is a
permanent, put it on the battlefield. If not, add
it to the hand. This continues until any
player doesn't wish to search for a card. All
libraries must be shuffled afterwards.
In Phyrexia, the fear of anything light is so strong
even the dim must be burned out.