I call this... The "Spiderbat Secret Passageway", or the ✨SSP✨ for short... It's a glitch I discovered so I get to name it what I want!!!

On the first floor a tile was deleted next to a door seemingly at random, but that happened because I deleted that tile on the previous save. Essentially, any block pushed on a previously open level, will continue to be pushed in the newly-loaded level. Conveniently I can ALSO use this to skip through the second floor, by pushing a secret on the previous floor that just so happens to entirely skip needing to go get a key for the locked door.

There's a bit more to it, what's not shown in this video is the setup I needed to get the save to delete that first block, which required me to turn on the ingame debug mode (Specifically to use the level-warp function), played E2L9 to push a certain secret, started Episode 4, warped straight to floor 5, then made my way to that same spot to push this secret in a particular direction, but also requiring to wait until two tiles had been pushed already. THEN I can start Episode 5 and have that particular tile be deleted. Boom, Spiderbat Secret Passageway!!