Masked HERO Blast (RATE-ENSE2)

Must be Special Summoned with "Mask Change" and cannot be Special Summoned by other ways. If this card is Special Summoned: You can target 1 face-up monster your opponent controls; its ATK becomes half its current ATK. Once per turn, during either player's turn: You can pay 500 LP, then target 1 Spell/Trap Card your opponent controls; return it to the hand.