From WiKirby, your independent source of Kirby knowledge.
Burn-Burn is a Power Combo usable by Kirby in Kirby 64: The Crystal Shards. It is a combination of two Burn abilities, and is obtained by combining either two Burn-yielding creatures or a Burn ability with a Burn-yielding creature. When using this ability, Kirby transforms into a fiery phoenix that goes forward a short distance and dissipates, leaving Kirby temporarily immobilized.
Unlike the normal Burn, Burn-Burn has a much greater range to its attack and travels much further. However, due to the aforementioned loss of control at the end of the move, it should be used with care.
Like the other abilities in Kirby 64: The Crystal Shards, this ability does not change Kirby's physical appearance in any way until it is used.