I enjoy these "collectathon platformer" games, like Spyro and MediEvil. In fact its resemblance to MediEvil made me interested in the game in the first place. 🙂
This one will keep you busy for about 5-6 hours. The level design is great, it somewhat reminds me of Rayman 3.
You would not be able to tell, but the game was mostly worked on by just one developer, a very impressive feat!
Besides showing how much the developer has managed to do on his own, I like that the credits have various screenshots of how the game looked throughout its development.

A few negatives then.
Some bosses are not that fun and overstay their welcome a bit too long. One of them even reappears later and you have to beat him in exactly the same way as you did before! 😒
As for the collecting aspect: there are 20 collectibles in each level and one hidden extra. Most are not very hard to find or are straight up on the main path. Unfortunately if you've missed one, you typically will not be able to backtrack to get it. Instead you will need to replay the whole level. There are no chapters for levels either. Annoying if you've only missed one or two collectibles like I have.

A recommendation then from me! Maybe pick up the game on sale if you have a problem with the game's play time.