This is Razor-Kai, one of the earlier Autozakretians, and he lost his life to depletion of energy whilst fighting off other Autozakretians to save his Zakretian predecessors - he was an "awoken" Autozakretian like Proteus is.

When an Autozakretian 'dies', their soul remains. The soul of the Zakretian that once was.

Razor was a first gen Autozakretian, their shapeshifting abilities were limited to weapons and armour, and their life expectancy was actually longer than the proceeding generations, 2nd and 3rd, Proteus is 2nd,

2nd gen had much better shapeshifting and selfhealing abilities, but the life expectancy was halved than that of the 1st gen. More 1st gen Autozakretians exist than any other.

3rd generation Autozakretians are the least successful because most of them were converted from inbred Zakretians, much later and closer to the extinction of the species.