I got it a couple of days ago on Switch for 6 bucks and I've enjoyed every second from beginning to end.
For anyone who doesn't know, Katana ZERO is a 2D action game based on trial and error. You play as a guy dressed like a samurai who can rewind and slow down time, and uses it to work as a hitman and slay everyone in his path. It's as cool as it sounds. Much like Super Meat Boy, Celeste, or Hotline Miami, you get to the level, you try to beat it and, if you die, time rewinds to the beginning so you can try again. Pretty straightforward, but it works like a charm.
The game is stylish as hell. The neon aesthetic and synth music is amazing and it builds a great atmosphere while you slice and dice anyone who dares stand in front of you. It's very satisfying to slowly progress through a level, memorizing what to do next in your sequence of attacks and then executing it all flawlessly to clean the room of enemies.
But that's not all, the storyline is super interesting. I won't go into details because it's better to go into it without knowing too much, but the writing and the twists are outstanding. The way the plot plays with your mind is something I wish I saw more often in videogames.
I really liked the dialogue system, too. You can interrupt NPCs mid-sentence and be a rude asshole, or wait for them to finish and reply as a normal human being. There are a few really fun interactions and I'd be interested in playing through it again choosing different options to see how the dialogue changes.
It's not a long game, but I feel like it was long enough. And I think there's an upcoming DLC to add more to the story, which is nice because I want to play around a bit more in this universe. I liked it a lot and I strongly recommend that you give it a try if you enjoy this kind of games.