Bayonetta

Weapons I recommend for all fights:
Shuraba+Durga(eletric). Charge attacks with Durga (holding ) do a great deal of damage, especially if you have only little attack windows you can use. A nice combo is , , , , .

1st phase: You start on one of two platforms. Attack his heads while dodging a lunge from his heads, in addition to fireballs and a sweep with the tail. Once he falls to the ground, jump down and press + followed by mashing to rip off one head. Now, he will fly to the outer part of the colosseum. After the sequence, jump down and make your way towards him by jumping from platform to platform and give him a beating with another climax.

2nd phase: Just repeat what you've done before. He will occasionally destroy the platforms, which can be repaired by using the Hour Glass.

3rd phase: After you reinvented his image the arena will change and you have 5 minutes to kill the rest of his body. His attacks consist of ramming, spike attacks with his tail, a fire breath and stomping. Show him the nice, sharp aspects of Shuraba until you can trigger the climax.