Witherstorm: Destroyer

While Witherstorm: Destroyer is on the battlefield: All creatures power and toughness become 0/0.
Witherstorm: Destroyer’s power and toughness are equal to the number of Obsidian Block tokens are on the battlefield, and all Obsidian tokens have indestructible.
{3}{b}{b}: Search your library for a Wither and add it to your hand, and then shuffle your library.
{x}{b}: Create a copy of target token X times.