Overall, this game is a pretty good game, on paper. The idea is fine and pretty creative, the art is really good for having been made in a weekend, and the music is also great. However, it's botched by the controls and physics.

The biggest problem I have, and one that everybody's already pointed out, is the double jumping physics, and I think I've been able to pin down what it is There seems to be a time window, from the time you press jump when you're on the to ground, to the top of your jump, where if you press jump, your double jump will be about the same height as your jump. If you jump after that time when you're falling down, or you don't jump at all and try to jump when you fall off a ledge, then you get a pitiful tiny hop that has almost no vertical gain. You can get used to this. I have. However, I still feel it makes the game far worse, because it reduces the versatility of the double jump. Instead of being a hugely versatile tool you can use to autocorrect your errors, you can now only use it in very specific situations, and only with intentionality, making it a far less useful and fun tool. I think this is because you programmed the game to only count a jump when you are receiving an upwards boost, and not when you're falling from that boost or falling in general. If this is the case, you should just make it so you you are considered jumping when off the ground, and therefore able to double jump anytime when you are off the ground. This wouldn't explain the fact that you are able to do the tiny hop when you miss the timing window, so maybe there's something more going on here. I don't know.

That's my main problem with the game. Besides that, here are some smaller criticisms/nitpicks:

- The collision on the blocks is wieird, and sometimes I would get stuck in the corner of a block

- The one part where I go inside the platform to jump over spikes instead of over it is annoying, because it's really hard to tell where the roof and walls are and it makes it that much more difficult to jump over the spikes.

- I wish this game had more startup and crouching frames before a jump. And maybe some dust particles. And some landing frames too. Obviously, nothing too long, because that would compromise that gameplay, but it would make the game feel a lot better. *

-The player Character has no midair animation. If he is standing still, he just stands still in the air. If he is running, he just runs on the air. It looks really strange. *

- You have to enter your username every time you enter the leaderboard, which is kind of annoying. The game could just have easily saved your username.

Overall, though maybe my review may not have showed it, I liked this game. As I said, I got used to the double jumping eventually, the art is great, as is the music, I love the player character's run cycle and idle animation. I also love the animation on the portals. The leaderboard provided the competitive drive to keep playing, and the concept of having to complete the same level while avoiding the other runners is great. There's just a lot to be improved upon, but that doesn't make it a bad game. (Edit: Wait I just realized both your art and music were taken from other people. Sorry for this mistake, the game's still fun and all, just wanted to mention it.)

*Obviously both of these would involve even more development time which you probably didn't have, so don't take them too seriously. Just small suggestions for maybe an update or for future games and such.