You can have any number of "The SpaceNinja Baltan Seijin Basical Version" on your deck.
[LV2] (When Destroyed) Bunshin: 1- Place one card from the top of your deck face down on your field and by putting one or more cores from your reserve onto them, during the game, those cards become "Cost 0, Family: Bunshin, <1>LV1 BP3000, Green core" Green Bunshin Spirits (Bunshin spirits can't be braved. They're discarded if sent back to the hand or deck).