Astium Photon Wave! (R)

You may only cast this card if your opponent has life 4 or less, and the 《Galaxy Exalt》you are [Transform] into has 1 or less soul. [Cast Cost] [Pay 2 gauge] Deal 4 damage to your opponent!!! This card cannot be nullified, and its damage cannot be reduced. If your opponent's life would become 0 by this card, it cannot be changed by your opponent's cards. (Unrevivable)