When messing around on early levels I found that if you go through the first door then leave the game you can rejoin and spawn in level 2. This glitch can save about 1-3 seconds in game

Here is the video

tried replicating it, doesnt seem to work..

I found a useless bug though. I call it the Instant Gun. Basically, if you avoid the gun by alligning yourself while not touching the gun, jumping and sliding to get past it, you will not recieve it, But as soon as you enter the next room you're given the gun. Useless and its just here for general knowledge, I guess.

me performing it after like 25 tries