Texto em português

A criatura alvo que você controla causa dano igual ao seu poder a cada outra criatura e cada oponente.

"No momento antes de sua execução, ela se deu conta do significado de ser uma piromante, de estar viva e de ser Chandra."

Rulings

The creature is the source of the damage, not Chandra's Ignition. For example, Chandra's Ignition can have a white creature deal damage to a creature with protection from red.2015-06-22
Use the power of the target creature as Chandra's Ignition resolves to determine how much damage it deals to each other creature and each opponent.2015-06-22
If the creature becomes an illegal target by the time Chandra's Ignition tries to resolve (perhaps because another player controls it or it's left the battlefield), Chandra's Ignition won't resolve and none of its effects will happen. No damage will be dealt.2015-06-22