Update 2023-09-06: Please see https://www.speedrun.com/kf2/forums/l2o4a for new information regarding this glitch.
Door Elevator is a glitch that allows you to clip onto the roof of a building you currently occupy (or on top of a wall in some cases). It is the principal method for getting out-of-bounds in this game. This glitch can be used anywhere that meets the following conditions:
- There exists a single swinging door (double doors will not work)
- There exists at least one unoccupied square of space beside the inside of the door (either side works)
Align yourself with either side of the inside of a closed swinging door. There needs to be enough room on the side of the door for you to get the proper distance from the door for this to work. Open the door while facing as far away from the door as possible and it should clip you to the top of the wall you are standing against.
Door Elevator was first discovered several years ago by Japanese players, but hadn't been used in speedruns prior to my routing several of these tricks into the Any% run. To my knowledge, this glitch was previously entirely unknown in English-speaking communities.
Here are the oldest examples I could find of the glitch online:
