You can Tribute this card; Special Summon 1 "Machina" monster from your hand or Deck, except "Machina Megaform". If a face-up "Machina Fortress" you control is sent to your GY while this card is in your GY (except during the Damage Step): You can banish that "Machina Fortress" from the GY; Special Summon this card. You can only use 1 "Machina Megaform" effect per turn, and only once that turn.