Labyrinth

Cumulative Upkeep - Sacrifice a land
Players can't cast creature spells or look at face
down creatures they control.
When Labyrinth enters the battlefield, each
player gains control of all creatures they own,
turns them face down, and rearranges them
randomnly. Whenever a creature attacks and isn't blocked, blocks or is blocked, it's controller turns
it face up, then pays its mana cost or sacrifices it.