There's an interesting idea here, marred by a lot of confusing choices, dark and inconsistent graphics, and lack of player direction / feedback.

The game doesn't explain how to play beyond the controls, it's hard to see what is going on, the menus don't have a clear flow, the controls are sluggish and imprecise. And that readme...

I just played a few times, but I didn't quite get how it all worked, the cats do look pretty though! One of them was particularly cute when sort of yawning. I'll break it in categories:

Main Menu

• Buttons look a bit weird to me, but I suppose this ain't the final version and you focused mostly on the action itself.
• The title written "World of Cats" seem to be in that pink color Unity goes when a texture/shader doesn't load.
• On Controller Mapping the actions texts got a bit crammed, more space between lines would make it more readable.
• I imagined the buttons with cat amounts meant to start the game, maybe making them in a separate category would make it feel more organized.
• On the Read Me, I didn't understand much of the purpose of the text. Took me a bit to understand some words and didn't appeal to me, but then, I'm not a cat person.
• The clouds on the background feel a bit jittery. Not sure what could be the cause.

Flight Demo

I didn't really get the purpose of this demo, it looks alright, but at the beginning it seems terrain has no colliders loaded, so I can go through mountains and even the floor. When I get back up above the water I start colliding with the ground.

Gameplay

• Collisions feel wonky. The cat doesn't feel like part of the scenery when walking on the mountains. Once I managed to kinda go through one the highest points of the arena, sort of like those "no clipping" cheats.
• At start my cat seems turbo-powered, I click forward and it flies around strangely.
• I didn't understand how score works, I just stay around under that circle in the mountain, sometimes the number in my triangle icon seems to increase, sometimes not.
• Cat movement feels a bit strange, as in if you walk to the sides it strafes in an uncanny way.
• When I hold right click to evade, the cat sometimes lies down and starts sliding through the ground.
• It's hard to aim attacks, the opponents seem to have a bigger hit box than mine.
• What does the  line with colored ellipses and a circle mean?
• The music doesn't fit a battle on the arena setting.
• I wish I could choose my cat.
• Framerate kept at about 85-95 on the 9 cats setting. The 300 really dipped it.

All in all, the ideas for an arena game are there, it really needs more polish and a more understandable scoring system. I didn't find an end to it, do you lose somehow? I tried checking what happened if I went into the water and I just went through it.

Hey! I do realize this is meant to be a comedic game, but I'm not sure just how far you want to take the parody, so I'll treat it as if it was a serious game.

A definite strength of the game is that it has cats. I mean, we both know that the internet loves cats, and so do I. Having a online multiplayer game based around cats is a great idea.

Another thing that could be a strength could be the whacky worldbuilding. I say it could be because right now it's very hit-and-miss for me. I laughed a lot at the description on your itch page, which was just super absurd and wanted to make me know more about the world this is supposed to be set in. The in-game readme however I honestly did not care for at all. I guess I just don't find speech impediments and other diseases all that funny. Also, apart from the game itself, there was no hints towards the lore in-game at all. Classic storytelling rule: Show, don't tell! Put up a sign to a coconut fuel station somewhere. How exactly does the sport drive the harvest of coconuts? Is it just an event that the working cat class loves to watch? Put some drones with cameras in your world that broadcast the whole spectacle. There are fun ideas here, but I'd love to see them elaborated a bit more!

(Also, you definitely missed the chance to call them "cathletes" and I'm very mad about that)

Now, let's talk about the challenges. The first and foremost thing: Running an online game is hard, especially if it's real-time based. You'll definitely need to pay for servers, as free servers probably have waay too much latency to handle a game like this. Since you probably don't want to make too much of a loss running those servers, you'll probably need to think about monetization. And you probably won't get away with that unless you improve the quality of the game a bit.

Presentation-wise, I guess you use assets from some asset store, which is completely fine, but you need to make sure your level of graphical detail is consistent. Right now, the cats are extremely detailed, while the island itself looks more as if it was from a PS2 game. And don't get me started on the UI elements in the main menu. I'm also not a big fan of the camera effect that happens when you look towards the sky.

On my laptop (which is in no way a gaming PC to be fair), the game had a pretty bad framerate. I guess a lot of that comes down to the detailed cat models. I wonder if you could add a setting to use less detailed models for low-end PCs, since you usually want to keep your entry barrier as low as possible.

Music loop got pretty repetitive pretty quickly.

Gameplay-wise, I found that the most successful strategy for me was to just try and find a good hiding spot on the cliffside, which gets very boring very quickly. Unfortunately for you, there's a rule of thumb that players will optimize the fun out of games, so you'll have to find a way to make more active (and fun) play also more optimal. A simple idea might be to add a knockout counter.

Does the color / alliance system have any effect on the gameplay so far? If so, I did not notice.

Oh, and also, maybe add win and loss conditions to your game.

To be honest, I did not get the point of the flight demo. It was kind of fun, but felt completely disconnected from the rest of the game. I guess that's supposed to be one of those "aerostatic fishing vessels"? If so, strengthen that connection! Maybe you can win coconuts in the brawl, which you can then use in the flying game to collect fish, which you can then use to buy upgrades for your cat, which you can then use to get more coconuts or something.

Finally, there are still quite a few bugs to fix. Most prominently, collision between cats and the surface are very wonky and at one point, I managed to hide almost my entire cat inside the cliffside. The circle indicating the cradle does not match up with where you can actually stand while still being counted as within the circle. Hitting enemy cats feels pretty random, but that might just be me being bad at the game.

Finally, one more idea: You could also just completely lean into the "so bad it's good" genre. Ignore the online aspect of the game. Instead, fill your world with whacky and absurd stuff. You can keep the brawl in, but make it even more whacky, give the cats stupid punny names like "The Catnapper" or something silly. Add a silly storyline and enough cutscenes to make it work. Go full ham. This game will most likely not end up being the next Fall Guys, but maybe it will end up the next Goat Simulator.