- For the cybernetically enhanced version of Ridley seen in Metroid Prime and Metroid Prime 3: Corruption, see Meta Ridley and/or Omega Ridley. For other uses of the name Ridley, see Ridley (Disambiguation).
The Ridley Robot is an incomplete robotic version of Ridley that was built by him, and is the final boss in Metroid: Zero Mission. The robot is said to be missing its walking and flying units, thus it has large cables coming out of its torso which are seemingly connected to an unseen interface, either for power, computer control, or both. It first appeared in the cutscene which plays when Samus infiltrates the Space Pirate Mother Ship for the first time; the scene consists of one of Ridley Robot's eyes opening, signifying that it detected Samus entering the complex.
BattleAfter Samus explores the majority of the Chozodia temple and the Space Pirate Mothership, she eventually reaches a large, dark chamber located several rooms behind the vessel's control bridge. This is where the mechanical construct, the Ridley Robot, is maintained. As the door locks behind her, loud, screeching, mechanised noises start to resonate in the room as the Ridley Robot uses its arms to crawl towards Samus' location, with its green neon lights glowing in the darkness. Eventually, the chamber lights up and the battle begins.
To defeat the Ridley Robot, Samus must fire Missiles or Super Missiles at a small, glass-encased panel on his chest, which resembles the weak spot of Meta Ridley. Only Missiles will damage it; Beam weapons have no effect. It attacks by launching fireballs, homing missiles and laser beams, along with a claw swipe. Noticeably, the Robot moves its head depending on Samus' position in an attempt to block her attacks.
If Samus collects all 100% of the hidden items prior to arrival, the Ridley Robot's offensive and defensive power will triple, making for a longer and more difficult battle than normal. Once defeated, Ridley Robot will shut down and cause the Mothership's self-destruct countdown to begin, leaving Samus with 7, 5 or 3 minutes, depending on the difficulty level, to escape the ship.
Because Beam attacks have no effect and Missiles are limited, the only way to regain them is by shooting down Ridley's own projectile missiles.
Yoshio Sakamoto: "Ridley made an image of himself to demonstrate his power by making that image as a powerful weapon. Incidentally, it is currently incomplete, and is currently at the halfway stage, becoming more massive once the walking unit and flying unit is installed." 
- It is quite possible that the Ridley Robot was the original version of Meta Ridley, possibly a prototype of some sort. This is supported by the fact that both share the same weakness.
- However, an argument against this theory is that the Ridley Robot has artifical intelligence, something a reconstructed Ridley wouldn't need.
- A counter argument is that the Ridley Robot is the Meta Ridley Exoskeleton, and was temporarily fitted with AI for weapons testing.
- Concept art from the Prime trilogy shows a massive mechanized Ridley with wings and an apparent pilot; this may be what Sakamoto alluded to, though it was never implemented in a game.
|Scanners||Scan Visor • Hand Scanner • Biohazard scanner • Award Scanner|
|Space Pirates||Aeromine • Crawlmine • Eye • Hover Bot • Jumpmine • Mining cannon • Mecha Ridley|
|Galactic Federation||Security Robot B.O.X. • FG II-Graham • FG-1000 • Fuse Hint Scanbot|
|Chozo||Autoad • Autom • Autrack • Databot • Diggernaut • Elysian • Floating object • Gunzoo • Helios • Proboscum • Robotsmall and Robotbig • Shirk • Steambot • Swarmbot (-G) • Tinbot • TPO • Vaporwing • Wallfire • ZipNMEBomber|
|Luminoth||Airthorn • Lightbringer • Lightflyer • Luminoth sentry pod • Mechlops • Mekenobite • Octopede • Rezbit • Sentreye (Corrupted)|
|Other|| Androids • Armored Bot • Artificial Intelligence • Cyborgs • Darkling • Drones • Golems • Guard Node • RB133 Auricrusher • Reflec • Security Bot • Shaktool • Statues • Suspensor platform • Turrets • Work Robot |
Drones, Workers, Hunters and Guards • U-ton • Lucky Darts • Desert Phantom • Samus Tank • Integra • Cyclon (Queen)