Bubsdrop

Bubsdrop is a well known trick in mirror temple's b-side allowing players to skip getting the first key by performing a precise jump. The trick is performed by going through the vertical screen transition in the long horizontal room in Central Chamber, then by performing a tiny jump ( 1 or 2 frames ) you can fall back through. Then, by dying either by retrying or by falling, you will be respawned on the right side of the room skipping the first key!