Yemachu

I've debated +10ing Knoll mostly because most of the red tomes that are plausible to +10 I don't have much interest in and he was the one I liked most.

Already had a +10 Lyon, who has a similar stat-line (and preferred weapon), so Knoll doesn't really do anything special for my barracks. Not that it matters; I like the Sacred Stones cast, and he could still be useful for modes like Arena Assault.

Building a green mage would have been more practical, as I don't have any merged beyond +3 (Boey), but most do not really stand out to me, and the ones that do tend to be 5-exclusive or seasonal. Might finish Boey. Also I'm planning to merge Orochi, but I don't have any copies to merge (yet). And with a bit of luck a nice other option drops soon.

I feel that, I try and get some of each type of unit but its sometimes hard to find one that I like and is easy enough to +10