You’ve seen them. If you’ve spent more than five minutes docking at the Citadel, you’ve definitely seen them. Those four-legged, green, insectoid silent workers scuttling around the Presidium, poking at holographic consoles and ignoring every single person who tries to talk to them. They’re Mass Effect the Keepers, and honestly, they might be the most unsettling thing in the entire trilogy if you actually stop to think about it. Most players just jog past them on their way to see Captain Anderson or Udina, but these mute maintenance bugs are the literal glue holding the galactic seat of power together. Without them, the station falls apart. Literally.
They don't talk. They don't fight. They don't even seem to care if a Geth invasion is happening five feet away. They just... keep working. It’s creepy.
The Secret History of the Citadel’s Janitors
When Shepard first arrives at the Citadel in the 2183 setting of the first game, the Council treats the Keepers like sentient furniture. They are a "protected species," which is basically a fancy way of saying "don't touch the equipment." Avina, the VI construct you meet near the Embassies, will politely remind you that interfering with Keeper activity is a crime. But why? Because nobody knows how to fix the Citadel. The Council races—Asari, Salarian, Turian—inherited the station. They didn't build it. They found it. And they found it with the Keepers already inside, scrubbing the floors and routing the power lines.
For centuries, the working theory was that the Protheans created them. It made sense at the time. The Protheans were the "ancients" everyone obsessed over, the ones who supposedly built the Mass Relays. But as we eventually find out from Vigil on Ilos, that’s a total lie. The Keepers aren't Prothean at all. They’re actually much older, and their origin is way more sinister.
Bio-Engineered Slavery on a Galactic Scale
The reality of Mass Effect the Keepers is that they are biological tools created by the Reapers. They are the ultimate "set-and-forget" maintenance crew. When the Reapers finish a cycle of extinction, they don't just leave the Citadel empty. They leave the Keepers behind to make sure the lights stay on for the next batch of organic life. It’s a trap. A giant, beautiful, five-armed trap.
Think about the sheer scale of that timeframe. We're talking millions of years. The Keepers have been resetting the breakers and polishing the walls for countless civilizations that we don't even have names for. They are engineered to be completely non-reactive to outside stimuli. If you kill one, it just melts. Its body contains a self-destruct mechanism—a chemical "dissolve" command—to prevent anyone from studying their biology too closely. A new one just crawls out of the bowels of the station a few hours later. Where do they come from? The Citadel’s core is basically a massive 3D printer for bugs.
That One Side Quest Everyone Remembers
Chorban. That frantic Salarian you find poking at a Keeper with a scanner. If you’re playing the first Mass Effect, this is your introduction to the mystery. He’s terrified because he’s breaking the law, but he’s obsessed. He wants to know what makes them tick.
If you help him, you end up scanning Keepers all over the station. It feels like a boring "fetch quest" until you get the payoff. Chorban discovers that the Keepers are essentially biological receivers. They are waiting for a signal. A specific "shout" from dark space that tells them to activate the Citadel’s hidden Mass Relay and let the Reapers in. This is the moment the game flips the script. These aren't just gardeners; they’re the doormen for the apocalypse.
Except, they didn't do it.
Why the Keepers Failed the Reapers
This is the part a lot of people miss in the lore deep dives. The Protheans actually won a small, quiet victory before they went extinct. A group of Prothean scientists on Ilos managed to survive the Reapers' initial purge by entering cryosleep. When they finally woke up, they realized they couldn't save their own kind, but they could sabotage the next cycle.
They traveled to the Citadel through the Conduit and messed with the Keepers' "programming." They changed the signal. So, when Sovereign (the Reaper vanguard) tried to signal the Keepers to open the relay at the start of the first game, the Keepers just... kept cleaning. They didn't hear it. They had evolved—or rather, been altered—to only respond to the Citadel itself, not the Reapers. It’s why Sovereign had to use Saren and the Geth to manually take over the station. The Keepers, the Reapers' oldest servants, accidentally became the reason the galaxy had a fighting chance.
Life on the Citadel: The Keeper Protocol
If you've ever spent time just watching them in-game, you’ll notice they follow very specific paths. They aren't random.
- Self-Regulation: When a Keeper gets too old or damaged, it wanders off into the maintenance shafts to die and be replaced.
- Non-Interference: They will walk through a firefight to reach a console.
- Total Silence: They have no vocal cords. No language. No culture.
It’s actually kind of tragic. They are a "living" species that has been denied any form of existence beyond labor. In Mass Effect 2 and 3, you see them less frequently as the focus shifts away from the Presidium, but they’re always there in the background. In the Citadel DLC for Mass Effect 3, there’s a hilarious and slightly horrifying moment where you can find a "Keeper 20" who is basically a local celebrity. It shows how the inhabitants of the Citadel have "humanized" these bizarre creatures despite them being completely alien.
The Evolution of the Model
From a developer standpoint, BioWare used the Keepers to solve a massive world-building problem: how do you keep a city the size of Manhattan (but in space) looking pristine without showing a thousand janitors?
The design of the Keepers changed slightly between the 2007 original and the Legendary Edition remaster. In the original, their textures were a bit muddier, making them look more like giant aphids. In the remaster, you can clearly see the organic-meets-synthetic details. Their skin has a weird, translucent quality. Their eyes are black pits. They look like something that was grown in a vat, which, as we know, they basically were.
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What Most Players Miss About Keeper 20
There is a specific Keeper in the Presidium that has become a bit of a legend in the fanbase. In the first game, if you talk to the right NPCs, you find out that people have tried to give the Keepers names or track their movements. One specific Keeper—often nicknamed "Keeper 20"—seems to be everywhere.
The dark irony is that the Keepers are constantly recording. They aren't just fixing things; they are sensors. Everything they "see" is technically data for the Citadel. While the Council thinks they are just getting free maintenance, they are actually living in a house where the walls have eyes, and those eyes belong to the very things designed to facilitate their genocide.
Can You Save Them?
In the ending of Mass Effect 3, the fate of the Keepers is basically tied to the fate of the Citadel. If you choose the "Destroy" ending, all synthetic life is supposed to be wiped out. Since the Keepers are bio-synthetic constructs heavily integrated into the Reaper-tech of the Citadel, they almost certainly die. If you choose "Synthesis," they presumably gain the same "understanding" and peace as everyone else.
But honestly? The Keepers probably wouldn't care either way. Their entire existence is defined by the task at hand. If the Citadel survives, they work. If it doesn't, they don't.
Moving Forward: How to Handle the Keepers in Your Playthrough
If you’re jumping back into the Legendary Edition or playing for the first time, don't ignore these guys. They are the barometer for the game’s tension.
- Do the Scanning Quest: Even if it feels tedious, talk to Chorban or Jahleed. It unlocks some of the most important "hidden" lore in the first game regarding the Reapers' true plan.
- Read the Codex entries: The game updates the Codex as you learn more. Seeing the description of the Keepers change from "harmless aliens" to "Reaper tools" is a great bit of narrative progression.
- Watch the background in ME3: During the final battle, or when the Citadel is moved to Earth, the presence (or absence) of the Keepers tells you a lot about who is currently in control of the station’s systems.
The Keepers represent the core theme of Mass Effect: the struggle between being a tool for someone else and having your own agency. They are the one species that never got their agency back, serving as a silent warning of what happens when the Reapers truly win. They are the ultimate ghosts in the machine.
Next Steps for Lore Hunters:
If you want to go deeper into the "automated" horrors of the Citadel, look into the history of the Citadel Core and the Control Signal lore found in the Mass Effect 3: Leviathan DLC. It recontextualizes why the Keepers were necessary for the Reapers' cycle in the first place and how the Intelligence (The Catalyst) views them compared to "useful" organics like Shepard.