This is a very good game. I had some trouble getting into it at first, but I'm glad I gave it more of a chance.

It's sometimes described as a cross between something like Slay the Spire and a tower defense game. It's not completely inaccurate, but I think it might push some players away. The game is less like tower defense and more like if you had to play 3 Slay the Spire battles at the same time.

This means that on any given turn you have quite a lot of options for what to do. Slay the Spire is a game about making a ton of tiny decisions throughout the run. Monster train is a game about making slightly fewer, but far more complicated and impactful decisions. This makes it feel more strategic than Slay the Spire in some ways because how you play your deck matters more.

I don't write many Steam reviews, and I don't like giving negative reviews in general. However, this is a game I can't recommend to anyone.

The concept is neat, but most of the levels aren't any fun. The first couple dozen are good, and then after that it just becomes incredibly tedious. The majority of them have only a single solution, and the developer has even gone through to explicitly remove unintended ones. So when you solve a level you don't feel particularly creative, you just feel like you pushed objects around in the precise way the developer wanted you to.

On top of this, a lot of levels are incredibly frustrating in that you have to do a series of multiple unintuitive things to solve them which means that even if you think you know part of the solution you still have to fight with the game in order to execute it and move on. This also makes it nearly impossible to play in tandem with another person because, unless that person was playing the game every moment with you or also playing on their own, they would never have enough information to be able to give you any useful suggestions.

The level order is also really bad. The game isn't gated heavily, and so at any time you have a decent number of levels available to play. On the surface this seems good, but now that I'm at the halfway mark I find myself wishing all these levels were in a much more explicit order based on the skills you've demonstrated as a player so that the difficulty curve wasn't so random.

~200 levels seems like a lot of levels, but this game has so many concepts that even with that number it doesn't feel like it would be enough to teach you all the things the game wants you to know to solve them. This game feels like it would have been better with half the number of areas and twice as many levels in each of them to smooth out the progression. I'm stuck on a few levels, and I really have no idea if going to a different area is going to show me anything that could become a hint for these levels so it feels like I may as well just look at a walkthrough or stop playing.

I don't regret buying this game, but I think most people should stay away from it. It's not the kind of creative fun experience that you might assume it is.

I do like this game, but I have a lot of trouble recommending it to anyone. The decisions the developer made here seem actively antagonistic to new players. I would have to link the game along with 3-4 different guides just to make sure whoever I recommended it to had a decent chance of enjoying it. If you have all the information it really is quite good. It's just that the game never bothers to give you the information you need in order to enjoy it.

Here are the things wrong with this game.

1) The tutorial is too hard. Instead of spreading the 3 tutorial levels out over time the game requires you to be able to execute even the advanced mechanics right from the beginning. I imagine some casual players may not even be able to complete these 3 tutorial levels. These levels also lack any kind of flow, and so they're also just bad levels in general.

2) The tutorial is too short. The tutorial doesn't explain some very key movement mechanics that are profoundly unintuitive to the point that they are literally the opposite of reality. There's a hidden "charge" system the game never explains that allows you to either dash or jump in mid-air. Not all of the cases where the recharges happen are explained and so the player is left without enough information to even begin to tackle anything past the first 15 courses. The player is forced to look up a guide online or spend a lot of time randomly button mashing in order to progress.

3) The "overworld" is dumb and confusing. Instead of the devs bothering to figure out which order the levels should be in the game has you exploring these 4 zones between the worlds in order to find new levels. Sometimes this requires executing extraordinarily difficult platforming tricks as well as a key obtained from doing really well on previous levels. The layout of this zone is very confusing, and it is very very very very very frustrating having to deal with a dumb mini-game just to get to the next course. The courses are hard enough on their own. I already did well enough on the courses in order to get the key. Just let me pick them from a menu, and don't lock content behind meaningless redundant skill gates you didn't think through properly before you implemented. It's very easy to get stuck.

4) Keys aren't explained. The game doesn't explain adequately how to obtain keys. This leads to being stuck until you look up a guide online that explains how to get more keys.

5) Key colors are difficult to differentiate. I'm a little bit color-blind. The game has like 5 key colors. I can only differentiate between silver and "the rest of them." They bothered to make the key icons look different, but not the locks. So good luck being able to figure out where to take a key you just obtained because a) the lock colors are all very similar and b) you might not even be able to get there due to point #3.

6) Character differences are not explained. 2 of them are quite similar while the other 2 are quite different from all others. It would have been nice to have been told by the game why I should ever choose a different character than the default.

In conclusion, I do like this game, but don't be afraid to look up guides on how the mechanics of the game work. It's really not fun if you don't do that.

I also want to reiterate again that the entire concept of The Nexus feels very much like the dev fell in love with their own "clever" idea, and never bothered to think through the ramifications of what they were doing. I'm sure it took a lot of time to build and design, but it only ever serves to frustrate and impede player progress to new courses. Just save yourself the trouble and look up a YouTube video that shows how to navigate to all the courses along with a map of door lock colors. You will have a much better time of it.