Use the power of the enchanted creature as the activated ability resolves to determine how much damage is dealt. If the creature isn’t on the battlefield at that time, use its power as it last existed on the battlefield. Note that this works differently than the fight keyword, which requires both creatures be on the battlefield for any damage to be dealt.

The enchanted creature is the source of the activated ability, not Burning Anger. For example, if the enchanted creature is green, you could activate the ability choosing a creature with protection from red as the target.