I've done 60 levels of the crystal cave and removed nails from 3 roots but journal still says i have 2 left though i couldn't find on on level 60 like i could on 15 30 and 45, is this a bug?
Personally I can't get the quest in either my older v4.4 save or a brand new v4.9 save. Perhaps in the new save I have to find one first? Anyway, I believe in the dev log you're supposed to be able to pull out ANY nails, so any 15 floors of any dungeon. In my v4.4 game I think I've found 3 or 4 of them and the fruit gives now 200 size? Hard to know.