wonder why he hasn't tried to make prostetic arms yet. even better, prostetic arm that shoots rockets and lasers!
He made some cool guns and all but they're still relatively straight forward mechanical objects he enhances with the magic/skills he got from monsters. An artificial arm that's of any use and doesn't just dangle from his stump would probably require some specialized designs and a particular skill I guess? Maybe he could do it right now if he used some for of transmutation to move it around but that sounds like it'd kind of keep his attention to it occupied a lot of the time, maybe it'd prevent him from using other skills at the same time?
I feel like he definitely will have either an artificial arm at some point or kind of go a bit monstery with a new acquired skill and regenerate. Of course, if I were a writer and gave a character regeneration long after they lost a limb and it had already healed over and all I'd say "Too bad, took too long," but I dunno what this author will consider acceptable or not.