Awesome! It reminded me of Geometry Dash in a good way!

Fun game, one small suggestion is to make the gun have some sort of cooldown or autofire mode (hold to shoot) because the game is a lot easier if you can click a lot faster which seems a bit unfair. I do love the simple art style and music though!

I really likes the saturated colors and how they contrast from the black background as well as the smooth lighting.

The sound effects of the enemies getting hit and the particle effects that come off of them makes them so satisfying to kill. I also like how the particles match the enemies, it makes it look like you're blasting chunks off of them.

I also liked how the game had different enemies to fight, though I was kind of hoping they would have more specialized attacks rather than having more health or shooting slightly faster. Perhaps you could have the enemies carry different weapon times, such as a shotgun that shoots a spread of bullets, a sniper whose bullet velocity is lightning fast, or a melee enemy that constantly runs towards you with a spiked bat.

I felt like the jumping wasn't that responsive whenever the cube was on a ramp or when the cube was standing on its corner. If the cube's rotation was meant to be a movement style choice, then perhaps a raycast boxcast that doesn't rotate can be used to determine if the box is grounded or not.

The jumping also felt kind of floaty, which made it frustrating to dodge bullets since my character would be stuck floating in the air while an undodgeable projectile would come towards me. I would suggest looking at the video, Better Jumping in Unity With Four Lines of Code. It really helped me understand how jumping in classic platformer games (such as Super Mario Bros) is satisfying and how to easily design the mechanic in Unity.

The rewind feature feels more of a secondary feature rather than the main ability of the game. Perhaps if there were more areas that required the rewind feature then it would feel much more useful. However, even if it's more of a secondary ability, it's still a REALLY cool effect watching everything travel backwards in time.

Cool game! This is the first non-puzzle game I've played on this game jam. If you want, then rate my game.

It was a fun game. Ireally enjoyed the aesthetics of your game, very simple but yet glowy and smooth. I did not use the rewind as much as i would like in game. But it was great. 

(Please rate mine :D) 

Fun game, I liked the simple art style. I will say, with the player having such a high move and jump speed and the enemies having so much health, I feel like the player is incentivised to just run past the enemies. I had a lot of fun with it though

The graphics are nicely done despite being simple, and the music and sound effects fit the game quite neatly. I agree with NilaCk regarding the floaty jump and bullet speed, and prehaps some screenshake in places could help the game feel if not overdone. 

I also felt that the rewind wasn't that useful. You said in an earlier comment that you didn't want to force it on people, but I feel thats not the correct approach. If a mechanic doesn't add to the game, it generally shouldn't be there in the first place. Thats not a hard and fast rule, but designing a core mechanic that people don't need to use is a little self defeating. I'd suggest reworking the mechanic a bit to tie it more into the gameplay and encourage its use.

But those bits aside, the game has a very fun base and is impressive for your first game. With some tweaking this could really be an excellent shooter.