Ok, so, the game is nice - especially when it comes to the gameplay. It's more on the casual side with very good flow - exploration felt really enjoyable and design on the location level is really intuitive. The overall map could have been more interconnected though - but the crutch of warping between checkpoints saves from too much backtracking.
The one big downside for me was the story - it started off with cringe millennial references and jokes, was ok in the middle part and took a nosedive in the end. Like, the whole environmentalist thing of "ferrox drilling spawns monsters - so it's bad" gets completely obliterated by the tone of the defalt ending. Cause even though the civilization has endured and the general mood of the post apocalipse during the whole story was more of the "hope for the future", in the end the "bad oil drilling" is required for even a semblance of a positive ending.
And the whole twist before the last boss felt like a cop out. And the entire Dustborough plotline is the worst offender - it's not even your typical Saturday morning cartoon level of brain dead - it's around and hour at least of setting up a cringe cartoon villain, and that all turns out to be a punch line for a Rick and Morty level joke. That was THE moment of genuine rage for me.
But story aside the game plays really good, and the great flow alone makes it an overall positive experience.

Great short little metroidvania

Biomorph is a great Metroidvania. The art style is very good, with both the characters and locations being very memorable. The soundtrack is great, with some tracks reminding me of Celeste, some of Hollow Knight, and others of Iconoclasts, three games I very much love. As others have pointed out, the game isn't the hardest. There aren't THAT many bosses, and the ones that do exist aren't that difficult to take down, even the final bosses. The bossfights were still enjoyable in my opinion, despite them not being too challenging. Where the gameplay really shines though, in my opinion, is the exploration. The game uses a golden border system to tell you when you've discovered everything there is to discover in a given room, and searching for all the hidden secrets was a blast. The game does start out a bit slow, as is the case with many metroidvanias, but as you explore more and get more movement tech and biomorphs, traversing the rooms and solving puzzles is a blast. The biomorph mechanic is very fun, though I will say some of the transformations felt a bit underutilized. You'd use them in a handful of very specific scenarios or puzzles and then never touch them again. Others felt borderline necessary. There's a creature that lets you walk on spikes in the first area of the game, and this ability is so useful that it never left my roster for the entirety of my playthrough. Still, intentional or not, using the different forms you collect to traverse the map in roundabout ways is super fun. The world of this game is also very interesting, and the characters and dialogue have a lot of charm. Overall, worth the money. I bought the game on its recent anniversary discount, but I think it's well worth the full price.