Starving Venom Fusion Dragon (MP17-EN147) Secret Rare

2 DARK monsters on the field, except Tokens
If this card is Fusion Summoned: You can make this card gain ATK equal to 1 Special Summoned monster your opponent controls, until the end of this turn. Once per turn: You can target 1 Level 5 or higher monster your opponent controls; until the end of this turn, this card's name becomes that monster's original name, and replace this effect with that monster's original effects. If this Fusion Summoned card is destroyed: You can destroy all Special Summoned monsters your opponent controls.