I'm not really sure what for, but I feel like runestones should have other uses. Maybe they would be donated to something or someone like a wizard (Star?) to improve certain things. Each level would improve the ability by a small percentage. Example:
Donate x amount of y runestone to increase z activity by xx%.
Donate x/xxx of runestone 11 to increase corn harvest by 0.01% (level 1).
Donate x/xxx of runestone 7 to increase truffle production by 0.01% (level 1).
Just trading magic for magic basically. Would be nice for late game players where the lava sphere isn't that lucrative.
