Short answer: I’m not an artist I’m a programmer
Longer answer: I’m not only not an artist, I also spent most of the time programming
Long answer: I’m not an artist, I have never been very good at making things asthetically pleasing and care more for functionality. That being said I do enjoy pixel art and making sprites. Which is why the menus look like crap but the actual sprites (bar jhin) look fairly decent. Jhin’s looks bad because his body is weird, with his shoulder thing, mask, half cape or whatever and twig arms/legs. I couldn’t find a good pose that would work for him shooting while keeping it distictly Jhin so I did the best I could.

If you’re referring to the walls being weird here’s why:
I saw it in a video that showed it off and I thought it looked cool and I wanted to do that. Have some sort of fake 3d environment that is very clearly not 3d at all. I personally like how it turned out, but a few people have complained about it (less than a 6th of the people who have played it) and no one except me seems to like that style more than the alternative. Should I continue development of this I would likely go through and redo it so it has smooth walls.