When you summon this Spirit, put three core from the Void next to your deck. The cores next to your deck can only be used by this Spirit's effect.
[LV1][LV2] (Either End Step) Send one of the cores besides your deck to the void or put it on one of your Nexuses. When the cores become 0, destroy an opposing Spirit/Ultimate, and return this Spirit to your hand.
[LV2] (When Attacks) Destroy an opposing Spirit with a Cost equal or lower than this Spirit's.
Rulings:
1. When there are 2 "The First Ultraman" on the same field, they cannot use the cores of each other's beside the deck (meaning each of them is still limited to 3 cores).
2. When this Spirit leaves the field, the remaining cores beside the deck are returned to the void, as there is no effect using them.