Sphere of Annihilation - Adventures in the Forgotten Realms Promos

Sphere of Annihilation enters with X void counters on it.

At the beginning of your upkeep, exile Sphere of Annihilation, all creatures and planeswalkers with mana value less than or equal to the number of void counters on it, and all creature and planeswalker cards in graveyards with mana value less than or equal to the number of void counters on it.