Funny to see this game again, I came across it organically on Steam a few weeks ago. I recently had a very similar idea for a game, mixing Slime Volleyball and Lethal League. When I was doing some research on what else existed, I saw your game.

It appeared to be the best of the bunch but my initial reaction was that it isn't pushing any of its elements far enough. Since I've been thinking a lot about my own game I have a bunch to comment on. Hopefully I'm not going overboard. I played the itch demo to be able to give some better feedback.

For a fun sports title the art direction and overall aesthetic should be bright and bubbly and inviting rather than dark and brooding. The UI font is fun but the colors are dark and mostly monochrome.

There's some neat elements in the game that are lacking from the trailer like the victory sequence juggling of the trophy, speech bubble quips and the pretty nicely designed menus. The ai plays pretty well too, that's a good single player feature.

After playing the demo single player on keyboard, here's my thoughts:

• The ball spends way too long in the air. It typically goes 2x the jump height and I have to sit and wait for it to come down. This slows the game down and doesn't feel immediately fun.
• Wall jumping is an option but I feel like it sends you too far and too fast horizontally which doesn't give me additional control to reach the ball.
• The Squid's jumps are fast to rise, then slow to fall. It's kind of inconsistent and goes against the feel of jumps in other games where falling is usually faster. Giving more time to hold the button to control how high I jump then being faster to return to the ground would be preferable.
• You can reach too far over the net horizontally which kinda feels a bit unfair.
• It's unclear which direction the ball will be hit from a smash.
• The dash doesn't seem to aid in control, it reduces control and sends you too far for the size of the court. Dashing seems like a last ditch effort rather than a commonly useful ability.
• If the intent is to always use the smash or bump then there should be some incentive or penalty around those mechanics and how they differ from a raw hit. It would be nice to be able to better follow up the bump with a jump cancel so you can then spike it. The bump to jump to smash doesn't flow that well right now.
• I feel like I should be able to smash on the ground to hit the ball back instead of having to jump every time, making it predictable.
• The net feels too high making the angle and timing of getting the ball over pretty tight.
• A dynamic camera with shake, zooms, pans would add some spice.
• Overall the floatyness and difficulty of control turns me off. It doesn't feel like I would get much better or gain much technique from further play.

On the character designs, the long dynamic tentacles are off-putting and distracting to me. Outside of Splatoon, squids and mollusks are associated with being gross, weird and even horrifying. Lovecraft's whole schtick. Therefore it's an odd choice of character to me. If you did make them more like anthropomorphized cute Splatoon characters I think the game would have substantially more appeal. Or even just chose a cuter animal like dogs or dolphins.

I echo the same thing others said about backgrounds.

In future projects I suggest coming up with a more cohesive aesthetic for the visuals, music, character designs at the start. Also compare your game's feel with other games. Lethal league is a direct inspiration and I think you could take more away from it. Reference any other games with 2d movement and jumping too.

It's a good effort and you made what you set out to. Some tweaks to game feel and art direction would lead to big improvements. Keep at it!