EDIT: Nevermind, I figured it out. Above 75 skills can only be raised by use, not by point allocation :)!

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My party is currently in Trynton, Upper Branches. I just saw the shaman on the seventh bough, then went east and killed some Oak Saplings. This gave me enough XP to level up my Fighter and my Gadgeteer, but when I did so I noticed that the Fighter's Sword skill and the Gadgeteer's Engineering skill were unable to be increased (even though they are only at 79 and 76 respectively). (*see attached screenshots*)

Does anyone know what is going on here?

Fortunately, raising Engineering to 85-90 isn't too hard. Just get the Regenerating Stone, stand on the flames in Arnika, and repeatedly use it.

Of course, you don't *need* such high skill levels until you reach level 18 and have found at least one of the ultimate gadgets. At your level, if you just use your gadgets whenever possible, you shouldn't need to spend extra time practicing.

It is worth taking a detour to get the Lazurite Stone, however, especially if you don't have a bard in the same party. You don't actually have to fight the boss in the temple; just use fake combat to pick up the stone and retreat before the round ends.