Better than 5e.
The book layout is a bit wonky, but the writing is concise and informative.
The mechanics are OSR-reminiscent at first, but classes and magic make it feel like a beautiful bastard child of 3.5 and 4e: in that there's no imbalanced arbitrary fuckery as in 3.5, and no copypaste-into-a-template feel of 4r.
Classes are called paths and are three tiered. There are no restrictions at all, you can take any, or even branch out horizontally and take another level 4 path at level 7 if you wish so. It leads to some of the combinations being retarded, but there are no trap options. Surely, just having common sense is enough to get yourself something at least decently playable.
Magic is pretty 4e-esque, but it doesn't feel a carbon copy fest. This game rather makes you excited about playing a build, because you can legit make almost any reasonable mixed archetype from fantasy work.
There are no skills, you just roll attributes against a fixed TN of 10.
Modifiers are handled 5e-like, with the system of boons and banes that work largely like 5e adv/disadv, but have more linear probability curves. Boons and banes past the first one give minuscule bonuses (because of diminishing returns) to the success%, so the book encourages the DM to assign them out liberally.
The game on whole is combat oriented, and it shows: things related to combat (paths, magic etc.) take up the majority of the book.
There is a corruption (i.e. sanity) subsystem that is fairly well developed with rather gory and macabre mutations that can be out of place or trigger someone's sensibilities.
Encounters are tuned hard. The game assumes certain familiarity with RPGs in general, and will punish you for stupidity, but not quite as harsh as OSR products, in my opinion.
All in all, it's very rules light and OSR-like in everything but combat, and for combat it's pretty options-crunchy, but the whole thing is made with elegance and focus in mind, which is a welcome rarity.