X-Ray Climbing is a technique that allows Samus to go Out of Bounds. It is mainly used while getting stuck inside of a door. Any% Glitched is one of the few categories that takes advantage of X-Ray Climbing.
To perform X-Ray Climbing, make sure to pick-up the X-Ray Scope. Get stuck in a door, and crouch. Use the X-Ray Scope, face the other direction and immediately stop scoping. If done right, Samus should now be forced into a standing position which moves her up by 5 pixels.