Seems like Axe Mastery is bugged. Got Lumberjacking to 45, but nothing seems to increase Axe Mastery. Attacking, using Mighty Chop, using Chop on the tree, using Mighty Chop on the tree, cutting logs into usable size for the old man, nothing. Messing around with Cheat Engine, it seems like the experience for Axe Mastery is tracked, but whatever's supposed to actually level it up just doesn't run.