Darkness Neosphere

[ Fiend / Effect ] This card cannot be Normal Summoned or Set. This card cannot be Special Summoned except by sending 1 Fiend-Type monster you control and 1 Fiend-Type monster from your hand to the Graveyard when your opponent's monster declares an attack. This card cannot be destroyed by battle. Once per turn, you can return all face-up Trap Cards you control to the hand. ATK/ 4000 DEF/ 4000