|X-Ray Scope Room, Brinstar
|Reveal the concealed, destroy game
When major glitches are permitted, X-Ray Scope is above and beyond the most powerful tool that can be used for completing the game due to its ability to, among many other things, modify memory values.
There are several classes of memory corruption that are possible with X-Ray, all of which usually require being Out of Bounds. Samus' position, the screen's scroll position, and the vertical and horizontal direction of the X-Ray beam all factor into which memory addresses are affected.
As seen in Any% Glitched, you can set the Escape Flag by activating X-Ray from a certain position in the Landing Site Out of Bounds area. As shown in Total's tutorial, if you fall down from the standard X-Ray activation area, you can still X-Ray upwards from the floor below, then navigate back inbounds.
You're also able to change the BTS value of blocks. This is used extensively in 0%, in the creation of the God Blocks, the creation of the Artificial Varia block, and turning the transition block in Cathedral Entrance into a valid one. This also happens if you X-Ray Climb with the block shuffler route in 4%, turning a harmless block in your path into a bad transition -- notably, this is the only known instance of being able to change memory while within the boundaries of the room, even if it's still outside of the room geometry (due to the concave nature of Landing Site).
There is also at least one known instance used where blocks themselves can be moved with X-Ray; the first portion of the Artificial Varia setup creates a "bridge" of solid blocks so that you can stand on it and complete the setup.
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