You can discard 1 card; send 1 Fiend monster from your Deck to the GY. You can send this face-up card from your Spell & Trap Zone to the GY; send "Infernoid" monsters with different names from your hand and/or Deck to the GY, up to the number of monsters your opponent controls that were Special Summoned from the Extra Deck. You can only use 1 "Void Apocalypse" effect per turn, and only once that turn.