Healing Reaction, how far could it go?

So, I'm starting this Urban Gods setting campaing and I wanted to make my Hero a Son of Hephaestus or Hestia and like an unstoppable tank, smth like Wolverine or Juggernaut lvls of "unstoppable"

But When it came to how to restore I wanted to get fancy. Say, Healing: Reaction: Contact with Fire + Immunity Fire.

So If I'm standing of open flames, the bad guy hits me and it deals to me a Rank 4 damage. If I start my next turn on the open flames, should I just roll the d10 and would I come back from that? Alternatively, if my hero went Unconscious and my ally Son of Apollo shoots at me a flaming arrow, would that also trigger the Healing roll?
(I know Regeneration would be a bit easier, but I just don't like dealing with conditions and being knocked down)

Are there other ways to apply smth similar?