I had a few ideas at the beginning, for which I tried to explore several avenues.
2 principal ideas ; a kind of decaying dog, consumed by fire ; or a lighting mecha ( armoured robot), but noting very original !
I ended up mixing my ideas by focusing on the element of fire.
Here are some of my silhouettes to start with
This character is an ancien mecha whose armor is no more than a carcass it’s no longer functional, yet it has been re-animated by a spirit of fire (the “internal blaze” of the first creature!), but which deteriorates the armor again and again. Maybe an intelligent/smart spirit living through the body it inhabit ?