101% glitch

The 101% glitch is an item percentage-related glitch in Metroid Prime 2: Echoes. If performed, the glitch enables the player to collect the Missile Launcher twice.

Method
When first entering the GFMC Compound, the player must approach the ledge in front of them. Normally, they would reach this ledge by progressing through the room, and launching on top of it with a nearby Kinetic Orb Cannon. However, it is possible to perform a Ghetto Jump. Before triggering the cutscene where Samus plays Squad Bravo's message, the player must approach the rock formation on the side of the ledge that resembles a boot and perform a Ghetto Jump. They should then climb atop the ledge, and be able to drop beside the Galactic Federation Ordnance Crate housing the Launcher. The cutscene can then be triggered, and after it's finished, the Missile Launcher will reappear, and can be obtained again. Both Launchers count toward the game's item percentage, and if all other expansions are collected, the item percentage will read 101%. A demonstration of the glitch can be viewed here:

With this glitch, it is possible to skip one of the other items and still have 100%. If all other Missile Expansions are acquired, the Missile Ammo counter does not rise above the limit of 250. The glitch can still be performed in the Metroid Prime Trilogy version of Echoes. However, to do it in that version the player will need to use the Scan Visor and use it to lock-on to the G.F.S. Tyr when performing the Ghetto Jump. A demonstration of the glitch in Trilogy can be viewed here: