They are a pain the second time around but can be done. I usually go into this battle with high magic defense armor, a good shield, and a strong weapon. When the fight begins you want to just zoom as close to possible to the first King to appear. I'd suggest Iron Flesh at this close range depending on your level.
Most of their sword attacks can be avoided at this close range, the only dangers are its grab attack, its scream like attack, and attacks from other Kings (it's rare that they'll attack when you are really close to another King but it can happen occasionally).