Wrong Warp

"Wrong Warp" is a Portal 2 glitch which is RTA-only and is, in short, caused by new duplicate triggers that are spawned in a map by loading a save in challenge mode, and thus cause unintended behaviour with change level triggers.

How-to

To perform this glitch, open any map that can also be opened in Challenge Mode as well as Single player. Throughout anywhere in the map (preferably close to the end), make a save. Now, go to the menu and open a map in challenge mode. Load the save, and the game will be thrown into a hyprid state where the game in some aspects considers you to be in Challenge Mode (particularly through commands), while you are not actually in it. Go to the end of the map, or where the challenge mode "end" would be, and walk/jump through it. You'll be taken to the next map instantly, but you'll spawn at a different position to usual, which will most likely be OoB and cause the portal gun model to disappear (although it can still be used). You will thus have performed a wrong warp.