Guardians are organic androids created by the Alimbics as security drones, patrolling Alimbic territories and eliminating intruders.
Guardians are similar to the Alimbics in appearance, bearing ashy grey skin and a single orange eye. The head is fitted with a variable weapons system, capable of mounting many different weapons, from Battlehammers to Missile Launchers, et cetera. Guardians typically travel in packs of three to five.
When a Guardian patrol finds an intruder, they lock all doors in the area and proceed to eliminate the target. Their large heads make it easy to score headshots, but they scurry like cockroaches. If one is carrying a weapon like the Battlehammer, for example, the best strategy (if possible) is to use the weapon's opposite. So if a Guardian uses a Battlehammer, it will be weak to the Volt Driver. Once all of the Guardians in the area are defeated, the doors will unlock. In some cases, defeating a Guardian pack will trigger mechanisms that reveal secrets, like new weapons, Shield Keys and such.
- Metroid Prime Hunters (First appearance)