On its own it is a fairly typical wizard academy light novel if a bit more brutal, but with many of the shounen action tropes there. Protagonist struggling with his powers in a dark world, collecting friends to fight against its injustices and deal with them head on. The characters are interesting, the world a lot darker then usual and accepting treatment on non-binary gender roles (especially for LNs were the effeminate muscle man crossdresser is all too often the joke character). Some great evocative environments in the final part. Bit predictable at the start.
As part of the Spellblades series it adds a bit of background to important side characters and forms an interesting mirror to Oliver with Godfrey being a talented heroic character and Oliver being a mediocre tragic (anti)hero.
Still, that also means the story lacks some of the elements that makes the main story so interesting to me. So while an entertaining read, it doesn't really add much to the series. A good read for fans of the series, but not a must read.