Melffy Rabbys - Chaos Origins (CORI)

If your opponent Normal or Special Summons a monster(s) (except during the Damage Step): You can Special Summon this card from your hand, then you can Fusion Summon 1 "Melffy" Fusion Monster from your Extra Deck, using monsters from your hand or field. If this card is Normal or Special Summoned: You can add 1 "Melffy" monster from your Deck to your hand, then if you added a Normal Monster, you can Special Summon any number of Beast monsters from your hand. You can only use 1 "Melffy Rabbys" effect per turn, and only once that turn.