$3.31 @ TCGplayer
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.)
If a source you control would deal damage to a permanent or player, it deals triple that damage instead.
If an effect such as that of Chandra’s Pyrohelix asks you to divide damage among targets, you must divide the unmodified damage before tripling it.
If you control two Cities on Fire, damage dealt by sources you control will be multiplied by 9. If you control three, it will be multiplied by 27, and so on.
While you control City on Fire, if a creature you control with trample would deal combat damage to a blocking creature, you must assign its unmodified damage. For example, a 3/3 creature with trample blocked by a 2/2 creature can have 1 damage assigned to the defending player. It will then deal 6 damage to the blocking creature (2 tripled) and 3 to the defending player (1 tripled).
