Collective Inferno - Lorwyn Eclipsed - 387

Enchantment

Mana Cost: {3}{R}{R}

Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.)
As this enchantment enters, choose a creature type.
Double all damage that sources you control of the chosen type would deal.

Mythic · Lorwyn Eclipsed · #387 (ECL)

Illustrated by YUE