All Devouring Void

Caster must sacrifice all cards except for lands. Caster HP is set to 6 until their next turn.
Activates on caster's next turn - All players' hp is set to 15, all cards are returned to their deck
and reshuffled.
After activation, players can no longer cast sorceries or instants without paying 1 hp.
Can only be prevented if all players set their
hp to 6. Can only be casted once.