@MelReinH @KandyKobra
Based on how his power was described it seems to basically be a combination of 'Overhaul' and 'Rewind' from BNHA, except you experience everything you rewind and keep some of that memory. In other words, it's fundamentally actually
not a healing power. However, in this medieval fantasy world with heroes and battles with demons, this power only manifests during a war- and the most obvious use for 'rewinding' individuals is of course healing.
So, basically, the only reason he's called a 'healing hero' is because nobody in the kingdom had the obvious(for a scientific civilization like us) idea to try and find out how this worked or whether its boundaries could be pushed. I mean, since all the other skills and powers run on mana, not reliving experiences, so it's clear 'heal' is not actually the primary skill of this power.
TLDR; this could all have been avoided with
SCIENCE!