An impressive effort for a single dev, Axiom Verge has a great pixelart style and banging music, and an interesting glitch mechanic that is integrated into the plot.

Unfortunately, the actual moment-to-moment gameplay can be kinda plodding. The level design lacks the tightness of something like Metroid and feels kinda sprawling, with a fair amount of backtracking killing the pace at times. Several of the bosses are interesting set pieces, but the boss fights tend to range from being uninteresting to downright annoying. The bullet-hell boss near the end is absolutely awful.

That said, the glitch mechanic is conceptually interesting and corrupting enemies produces a variety of effects. The whole 'minus world' thing is cool as well. Sadly, a lot of the glitch mechanic just ends up being fairly standard Metroidvania progression fare, glitched blocks or patches blocking off exploration until you have the right tool to deal with them.

And that's sorta the problem with Axiom Verge. It has a lot of interesting ideas, but in practice never really rises above a formulaic, merely acceptable execution of them. It's not a bad game by any means, it's just not particularly exciting, and perhaps could benefit from a more collaborative effort where other people could lend their expertise to Tom Happ's ideas. Of course, maybe the sequel improves on this - I don't know, because I haven't played it yet.

I will say, though, that even though I have no intention of using them as the base game didn't interest me enough to want to play it again, the in-game addition of Speedrun and Randomiser modes is pretty cool and I wish more games did this.