A character who changes their being throughout the story through traumatic experiences and events

Ok so it sounds generic as heck, but bear with me. My character has an ability to regenerate, and he goes through difficult fights and situations that he can’t win but must deal with them regardless, and he’ll lose them but come back stronger.

However, it isn’t HE that comes back but an aspect of him developed into a personality. So for example if he was fighting for his life, through blah blah blah circumstances and events.

He will lose (always) and get severely injured and he’ll have a type of amnesia ( it doesn’t exist irl I just made it up for the story) that he forgets himself completely, and through the initial moments and experiences this new person has, their personality is formed.

I plan on doing this a few times, and the reason why is to explore different personalities and how it is both nature and nurture that shape a person. It of course won’t work if they completely forget everything. They’ll remember certain things like bits of their previous self’s values, like a desire to help others when they’re oppressed. They won’t however be the previous person they were.

To explain: they may feel the urge and need to help others who are oppressed, but when faced with consequences or resistance, they may cower and run rather than fight. This would be because they don’t have those same values, but rather a small whisper.

Plz guys if you have any criticism give freely