Zone of Sloth

When an opponent casts a spell and it isn't their
turn: Put a charge counter on Zone of Sloth.
Spells of mana value X or lower without flash and Activated Abilities your opponents cast or activate
can only be cast or activated as a sorcery. (X is the
number of Charge Counters on Zone of Sloth)
(Mana Abilities and Triggered Abilities still activate
at their normal speed.)