It's so funny to imagine this.
Like, I can't even imagine the destruction on some levels. Five Kaidos would just EVAPORATE whatever was in front of them, especially after the power scaling Egghead's given us.
Regeneration doesn't matter if the crazy drunk dragon oni man launches your old Gorosei ass a mile off the island with a Thunder Baguya.
The idea of five Kaidos is so comedically terrifying, just imagine the Gear 5 faces if FIVE KAIDOS showed up at Marineford. Lightning and flames and blades of wind raining down while your soldiers go flying all around like bowling pins.
I want a One Piece what if movie that's Kaido kidnapping Vegapunk and making clones of himself to destroy the world, and the entire movie is just Kaido destroying everything in his path while laughing his ass off.