So, a few notes. The jump only reset if the middle of the box sprite hit the ground, which wasn't always the case. On the second level, I got stuck right before the end because I jumped and landed in the gap between the bridge and the ground and then could move. I also found it weird how the mechanics weren't actually explained? I spent like 3 mins on level 2 because I didn't realize you could pick up the box, and then I spent another 3 minutes sitting there cause I didn't realize you could throw the box with momentum. Sound effects would be lovely and would add a lot to the game, and I think an end screen would be great, since winning only takes you back to stage 2. The time travel mechanic could also be explored more, but all in all I think you did a nice job so well done!