personally, i found it best to level up defense all the way to bonus first. That way you can get 2 level ups each level, and kill almost anything because the enemies will do 0 damage. then you use your points for anything =D
@erikthebrave: it depends on how many journey stone fragments you have. you need to kill fearsowers to get them. they are on every level.
portal scrolls are dropped on every odd numbered level.
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