Coven of The Restful Lily

Whenever a creature enters the battlefield under an opponents control, create a Treasure token.

Sacrifice a Treasure: Tap target creature and put a stun counter on it.

At the beginning of your upkeep, create an amount
of mana in any combination of colors equal to the number of Treasures you control. Until end of turn, you don't lose this mana as steps and phases end.