Dyrem
This Adaptability skill is quite useful for overcoming plot holes or out of character scenarios. Like how he didnt care that he was killing someone. Lots of authors gloss over that and say, “well his life depended on it” or something, but that doesnt feel realistic. This ability really help smooth those things out. I applaud you author.
I think that doing so (moving around the battlefield) would be quite cool. After all, in order to move freely enough, you have to be strong or of a certain skill level. Would be interesting to see him interfere with multiple points in the battle, turning the tides, and also being like a presence you can see but can't catch. I'm thinking Kuroko-esque play. but maybe I'm thinking too much down the line of an assassin.