- 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 (AKA Mecha Ridley) 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.
BattleEditAfter 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.
Samus must first fire Missiles or Super Missiles at a small, glass-encased panel on his chest covering a weak point resembling Meta Ridley's. Once broken, direct damage can be dealt on the Robot. Only concussive weapons will harm 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 Robot was a prototype, serving as a testbed for the technology later implemented on Ridley's body to create Meta Ridley. This is supported by their shared weakness and overall mechanical aspects. This theory is further supported by the fact that Zero Mission is, chronologically, a prequel to the events of Metroid Prime, where Meta Ridley is featured.
- The Space Pirate Mothership's alarm is active throughout the entire battle against Robot Ridley. It stops as soon as the robot is defeated.
- The glass panel covering its weak point is seemingly made out of the same material as Mother Brain's glass canister. Both strictly require concussive weapons to shatter.
- 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.
|Bosses in the Metroid series|
|Metroid||Kraid • Ridley • Mother Brain|
|Metroid: Zero Mission|| King Worm • Mua • Kraid • Kiru Giru • Imago • Ridley • Mother Brain • Ruins Test • Ridley Robot |
|Metroid II: Return of Samus||Alpha Metroid • Arachnus • Gamma Metroid • Zeta Metroid • Omega Metroid • Queen Metroid|
|Super Metroid||Torizo • Spore Spawn • Kraid • Crocomire • Phantoon • Botwoon • Draygon • Golden Torizo • Ridley • Big Metroid • Mother Brain|
|Metroid: Other M||Brug Mass • Fune and Namihe • Groganch • King Kihunter • Mystery Creature • Goyagma • RB176 Ferrocrusher • Rhedogian • Vorash • Ridley • Nightmare • Queen Metroid • MB • Phantoon|
|Metroid Fusion||Arachnus-X • Elephant Bird • Zazabi • Serris • B.O.X. Security Robot • Mega Core-X • Scientist • Yakuza • Nettori • Nightmare • Neo-Ridley • SA-X • Omega Metroid|
|See also: Bosses in Metroid Prime Series|
Little birdie • Mystery Creature • Neo-Ridley • Fake Ridley • Ridley-2
Ultrathermal Flamestrike Projector
Multi-Missile System • Phazon-enhanced armorskin
Vs. Meta Ridley/Meta Ridley • Omega Ridley
|Scanners||Scan Visor • Hand Scanner • Biohazard scanner • Award Scanner|
|Space Pirates||Aeromine • Crawlmine • Eye • Hover Bot • Jumpmine • Mining cannon • Ridley Robot|
|Galactic Federation||B.O.X. Security Robot • FG II-Graham • FG-1000 • Fuse Hint Scanbot|
|Chozo|| Autoad • Autom • Autrack • Databot • Elysian • Floating object • Gunzoo • Helios • Proboscum • Shirk • Steambot • Swarmbot (-G) • TPO • Tinbot • 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 • Kamer • RB133 Auricrusher • Reflec • Security Bot |
Shaktool • Statues • Turrets • Work Robot • Drones, Workers, Hunters and Guards • U-ton • Lucky Darts • Desert Phantom • Samus Tank • Integra