Letter Escape
Letter Escape, also known simply as the letter glitch, is a glitch in the Metro Kingdom that allows the letters in the park to be clipped outside of their normal bounding area, allowing the kingdom to be explored freely with them. This leads to all sorts of strange behavior, including letters interacting with elements they are not intended to, clipping through walls, and obtaining massive amounts of speed. The glitch was discovered by glitch hunter Syrkl.
Explanation
Normally, the letters are bounded by an invisible barrier surrounding the section of the park where they are located, and this barrier prevents the letters from roaming the kingdom freely.
While a letter is being captured, if the player ever gets too close to another letter, that letter will exert a force on the letter being controlled by the player in order to prevent the two letters from clipping into each other. However, this force can be abused if the letter being controlled by the player is near the invisible barrier, in order to push the player's letter through the barrier. This can be done by arranging the various letters so that one letter is directly between the boundary and another letter, with the two letters often clipped partially into each other.