Type of small bipedal walkers from the Metal Gear series.
"Gekko was an unmanned autonomous fighting vehicle developed by AT Corp for use in ground combat. Officially designated IRVING by the United States Army, Gekko were colloquially called "lizards" after the species of small lizard with a similarly spelled name: gecko. These war machines were created using a combination of technologies used in the production of Metal Gears REX and RAY. However, Gekko were not Metal Gears. Unlike true Metal Gears, Gekko had no nuclear launch capability. Instead, they were more akin to infantry fighting vehicles, with multiple units acting as a coordinated team in support of ground forces."