There are fighting sections where spells with advanced vocabulary are used. Personally, I skimmed through them.
If you care about furigana, beware that it randomly disappears for the entirety of chpter 4. It seems that volume 2 takes a mixed approach, putting furigana only in relatively uncommon words.
Harsh experience due to advanced vocabulary without furigana
I went into this series with insufficient japanese knowledge (just passed N3) because I stumbled upon the volumes. It didn't really matter most of the time, since there are long sequences of action with little dialogue. In general it has been very enjoyable for me: the pacing is fast, so I always felt rewarded without having to struggle too much. However, two instances were very painful: