Interesting game! I like the graphics of the game. I especially love how you graphically implemented the rewind mechanics.
The models were really well made, despite them being so simple. I was impressed by some shaders you made for the game. Particularly, I loved the player model T-posing, when the player save his position!
As for the game play, I think it would've been better if you made the character be able to freely move around in the actual game, like in tutorial. I actually found the game a little too challenging. Because the character move automatically itself, I was given almost a very little amount of time to think about what I can do.
Something minor that I kind of wish that you made better were the animations. In the tutorial sequence, when I tried to move diagonally, the character feet seemed as little odd. A shooting animation would also be a nice addition to the game.
But still overall, a great, fun and challenging game!