You can target 1 other card you control; destroy it, and if you do, add 1 "roid" card from your Deck to your hand. If a "roid" monster you control battles, during damage calculation: You can send 1 "roid" monster from your Deck to the Graveyard; switch the original ATK and DEF of your battling monster during that damage calculation only. You can only use each effect of "Megaroid City" once per turn. You cannot Special Summon monsters from the Extra Deck the turn you activate either of this card's effects, except Fusion Monsters.