A Zip line is a mode of rail system transportation present throughout Kraid's Lair in Metroid: Zero Mission. Resembling ziplines, they are used to cross distances hindered either by Acid or some other means. They only require a free hand to use, but Samus must activate their power station, the ancient Chozo machine by standing in its generator in Morph Ball mode, giving it a kinetic charge that reactivates the system. Samus can then shoot red switches on the ceiling to summon them. Samus can also hang onto them in Morph Ball mode, which is particularly useful for getting across long distances. It is unknown how the mechanism can hold the Morph Ball, but it is possible that there is a magnetic connection similar to the Spider Ball and a Spider Ball Track. One notable use of the mechanism is in the battle with Mua, where Samus has to grab hold of it to zoom past the creature when it tries to ram into her.
They are only named on the back of the Metroid: Zero Mission boxart.
- The Zipline systems of planet Elysia in Metroid Prime 3: Corruption is similar both in function and name.