The Sōzō no seinaru yari or the holy lance of creation is a powerful attack that only cass can use as the creator of the flipside

After his soul was reconstructed and he was sent back to the real world He left a gift that turned into a new version of the original puppet that cassidy would possess in the real world and gifted him the lance to be his main wepon

On its own its just a normal lance that can be thrown quickly and recalled to puppets hand just as quickly as it was thrown, but when puppet engages his final strike all of his magical energy is forced into the lance creating a giant beam of pure energy that can destroy anything it makes contact with within its radius

Because of how powerful this attack is it's locked behind a set of seals that only fredbear can break ensuring the attack is only used when absolutely necessary thus making fredbear the master of the puppet allowing him to keep a power like that safe from the wrong hands