Fortitudo, Bringer of Flame (Achievement/Tropy)

Fortitudo, Bringer of Flame is an achievement/trophy in the first Bayonetta that is unlocked by defeating Fortitudo on any difficulty.

Description
"Defeat Fortitudo on any difficulty"

Guide
Just beat Fortitudo on any difficulty. If you are struggling you can be on Easy or Very Easy

Here is the wiki Walkthrough (Normal Difficulty)