Cyber Shadow Gardna

During your opponent's Main Phase: Special Summon this card as an Effect Monster (Machine/EARTH/Level 4/ATK ?/DEF ?). (This card is also still a Trap.) When an opponent's monster declares an attack that targets this card: The ATK/DEF of this card become the ATK/DEF of the attacking monster. Once per turn, during your opponent's End Phase: Set this card in its Spell & Trap Zone.