On which game versions is regen bugged where you can't get it? I'm on 0.1.5d and I am pretty sure I have all the requirements but I haven't gotten it yet.
Can confirm that I also got it in this version, I'm pretty sure I got it dying in the caves, maybe dying in a fight is a requirement to first get it? I remember Graham said something to the effect of "I can't go down like this" when I got it
Edit: There's instructions of how to get it in the wiki, spoilers of course so click it if you want: https://learning-curve-rpg.fandom.com/wiki/List_of_Skills