Dismiss spirits to get their cores.
In Super Smash Bros. Ultimate there are plenty of Spirits to find and add to your collection, but you don’t have to keep every single one of them. You can also Dismiss these characters from your roster to send it back to where it came from. In return for doing so, you will receive a Spirit Core and SP.
There are some things to take into consideration when dismissing Spirits though. Some of them are very integral to opening new pathways in World of Light so tread carefully as dismissed spirits cannot be used after they’ve been discarded. In exchange for that are the cores which can be used to summon other Spirits, assuming you have the cores necessary to do so.
Getting cores via this method can be done in the collection section of the Spirits menu. Simply go into your collection and head to the Dismiss section. Once there you can select which Spirits that you want to dismiss. If you’re dismissing an exceptionally high level spirit the game will give you a warning before proceeding. You will also be able to see which the amount and which type of cores you will be receiving by dismissing the spirits as well as the amount of SP you will get.
Once you have these cores you can then go back into the main spirits menu and then summon other spirits with those cores. Different spirits that you can summon will have specific cores that you need to have to summon them.
Getting cores is quite easy in Super Smash Bros. Ultimate as World of Light and the Spirit Board have plenty of spirits to capture. However, getting their cores will be at the expense of actually being able to use them again.
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Attack of the Fanboy / GAME GUIDES / Super Smash Bros. Ultimate How to Get Cores