Mortal Shell is a "good" game, I can say that.
The concept of shell hardening is really satisfying and the combat is really smooth but that's about the only good thing this game has going for it.
Janky cutscenes, unnecessary animations (after crawling out a tunnel), extremely tedious back and forth gameplay (reminiscent of Alien Isolation), level design was super boring with so many large areas with absolutely nothing in it and a large number of items were quite redundant.
The bosses are also way too passive. So much so that I've died more to the basic enemy ganks than all the main bosses combined. As a matter of fact, I've only died to the tutorial bosses while still learning the controls.
Once I got to all the main bosses, they were a bunch of pushovers with little variety to their movesets.
I understand it's a small team but I'm sure nobody would have mind if they delayed the game a few more months to work on it more.
I don't hate the game, i had my fun with it, but it's not a game I'll play a NG+ of, after knowing just how boring it is.