Well obviously since Imusaturn easily handled 6 top tiers at once without struggle and easily low diffed a PK level character. Imagine Imu on his real body or whatever he's supposed to be in the 1st or 2nd world. Idk if this is just WG propaganda but Joyboy lost to their forces.
I think
@Elder Lee Hung isn't quite wrong when he's scaling the 20 kings very high. The Gorosei are very far descendants of the same kings and look how strong they are. So I'm sure the original 20 kings were even more powerful, let alone Imu who later reign supreme over all of them.