Union Activation (MZTM-EN023) - Maze of the Master 1st Edition

Send 1 LIGHT Machine Normal or Union monster from your hand or Deck to the GY and add 1 LIGHT Machine monster with the same ATK but a different original name from your Deck to your hand. If you Special Summon 3 LIGHT Machine monsters at the same time, while this card is in your GY: You can banish this card; add 1 monster with 3000 or more ATK from your Deck to your hand, then immediately after this effect resolves, Normal Summon that monster. You can only use each effect of "Union Activation" once per turn.