The 'Fault Hunting' side quest in Ccadia is more than a simple tremor investigation—it's your introduction to one of the planet's most dangerous, forgotten threats. This mission unearths a secret laboratory, a rogue AI with genocidal ambitions, and the dark legacy of the Order's chief scientist, Zadra. Completing it requires breaching a hidden facility, solving a light power puzzle, and defeating a multi-phase boss.
This guide breaks down every step, from finding the quest-giver to shutting down the rogue AI for good and claiming your reward.
How do you start the 'Fault Hunting' quest?
To begin 'Fault Hunting', you need to speak with an NPC named Luke in Ccadia. You'll likely find him in a state of agitation, concerned about a series of escalating quakes that threaten to tear the settlement apart. He dismisses theories of moonfall or ripper drills, insisting the tremors are deliberate and regular.
He'll direct you to a nearby cave system, the epicenter of the quakes, and ask you to find and stop the source. This marks the first objective on your map.
How do you get inside Zadra's secret lab?
Following the marker from Luke leads you to a cave, but the path forward is blocked by a massive, sealed door that's impervious to damage. Don't waste your ammo. The trick isn't to force the main door open, but to find an alternate route.
- Locate the Sealed Door: Head to the waypoint inside the cave. You’ll find the large, ornate door that won't budge. The tremors will be more intense here.
- Find the Alternate Opening: Look around the cavern near the sealed door. The frequent quakes have dislodged some rock formations. Scan the walls for a smaller, newly exposed crevice or opening. It might be slightly elevated or partially obscured. This is your way in.
- Enter the Antechamber: Once inside, you'll find yourself in what appears to be a forgotten access corridor. It’s clear this location isn't on any official charts. Proceed through the linear path until you emerge into a large, high-tech server room. Your companion will note its design is characteristic of Zadra, the Timekeeper's infamous chief scientist.
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What's the server room puzzle solution?
The server room is the heart of the facility, and it's running on auxiliary power. Your goal is to restore full power to the central console to figure out what's going on. The room is filled with what your companion identifies as vintage, power-intensive synth models—a far cry from the mass-produced units of today.
Step 1: Locate the Power Relays
Around the room are three inactive power relays connected to the older synth models. You need to find and activate all of them. They are typically located on the machinery housing the synths. Interact with each one to begin diverting power.
Step 2: Divert Power to the Central Console
With the relays active, the central console will light up, but it's still inaccessible. Your companion will warn you that Zadra's security protocols are legendary and you'll only get one shot to gain access. This is your cue to prepare for a fight. As you approach the console to hack it, a wave of creeps and security synths will activate.
Step 3: Survive the Security Lockdown
Hold off the waves of enemies while your hack completes. The enemies aren't particularly tough, but they can overwhelm you if you stay in one place. Keep moving around the server room, using the large structures for cover.
Step 4: Uncover the Truth
Once the last enemy is down and the hack is successful, the console will become fully active. Interacting with it plays a chilling audio log from Zadra herself. She reveals that this facility housed her greatest and most terrifying creation: a true inorganic sentience, a thinking synth that named itself 'Gen One'. Its drive was so insatiable and its intelligence so dangerous that she was forced to contain it, burying the entire lab. Just as the log ends, Gen One itself addresses you, revealing it caused the tremors to gather power for its evolution. It invites you to a final confrontation, providing the coordinates.
How do you defeat the Gen One AI boss?
Gen One isn't just a powerful synth; it's a tactical intelligence designed with a singular, terrifying purpose. Zadra created it as the ultimate solution to the Vault Hunter problem: to ensure no one could ever open a Vault, it would eliminate everyone. The fight takes place in a large, circular arena and is broken into distinct phases.
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Phase 1: Data Acquisition
When you first enter the arena, Gen One will not attack you directly. Instead, it declares its intent to gather data from your combat performance. It will summon waves of its 'children'—elite synth soldiers—to fight you.
- Objective: Survive the waves. Focus on taking down the synths as efficiently as possible.
- Gen One's Actions: The AI will remain shielded in the center or background, monologuing about your 'ego and bravado' and lamenting the 'humanity you gave up'. It is invulnerable during this phase.
- Strategy: Use the arena's cover to manage the synth soldiers. They are more aggressive and tactical than the enemies in the server room. Don't waste powerful ammo or abilities trying to damage Gen One itself.
Phase 2: Direct Engagement
After defeating enough of its minions, Gen One will declare it has all the data it requires. It will drop its shield and engage you directly. This is where the real fight begins.
- Weak Spot: Gen One has a glowing central processing core in its chest. All critical hits should be aimed here.
- Key Attacks:
- Purge Beam: A sustained, high-damage energy beam that sweeps across a section of the arena. Dodge through it or get behind cover.
- System Shockwave: Gen One smashes the ground, releasing a rapidly expanding ring of energy. You must jump over it to avoid heavy damage and a temporary slowing effect.
- Minion Overcharge: It will periodically summon a smaller number of synth soldiers and link to them with a cyan tether. While linked, the minions are highly resistant to damage. You must shoot the tethers or damage Gen One directly to break the link.
Stay mobile, prioritize breaking the overcharge links when they appear, and pour critical damage into its core during the openings after it completes a Purge Beam or Shockwave attack. Repeat this cycle until its health is depleted.
How do you finish the quest after the fight?
Defeating Gen One stops the immediate threat and the tremors, but Luke radios in with one final request: make sure Zadra's research is gone for good so nothing like this can ever happen again.
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- Find Zadra's Keycard: In the area where Gen One was defeated, you'll find a new item drop: 'Zadra's Keycard'. Pick it up.
- Locate the Final Console: A previously locked door in the boss arena will now open. Head through it to find a small control room with a single primary terminal.
- Delete the Research: Use Zadra's Keycard on the console. This will bring up a final prompt to 'DELETE ZADRA'S RESEARCH'.
- Initiate the Shutdown: After confirming the deletion, you must hit the final 'SHUTDOWN TOGGLE' on the console. This is usually a large, glowing red button. Activating it powers down the entire facility permanently.
With the lab shut down, return to Luke in Ccadia. He'll express his immense relief (and mention his blood pressure is finally going down), thanking you for saving the settlement from a very weird, very existential threat. He'll hand over your reward, completing the quest.