During stage 3 where the bouncing slimes making runs slower and more tedious there is a glitch to make them disappear. Basically the game spawns in the slimes when their spawn point reaches your screen and when an entity leaves the screen it despawns. Using this if you do specific jumps as seen in both DataFry's and my runs you can force the slimes to spawn high enough to the point where they jump off the screen, despawning, allowing for faster runs.

This glitch can be utilised once during any% runs and twice during 100% runs to allow for maximum run speed