Borderlands 4 One Fell Swoop Walkthrough

One Fell Swoop is the 5th main mission in Borderlands 4 (BL4). This walkthrough will guide you through all objectives of the One Fell Swoop Main Quest.

• Starting Location: Kairos > Dissected Plateau > The Stubs
• Quest Giver: Zandra
• Unlock Requirement: having finished Main Quest 4: A Lot to Process
• Recommended Level: 7
• Reward: XP, Money, Eridium, Rare Sniper & Devourer Weapon Skin
• Quest Description: A secret weapon, defenses that can’t be breached, and a singular goal to return to the Timekeeper’s side – you’ve ruined Sol’s plans more than once and there’s only so much a man can take…

Objectives:

1. Reach Sol’s production facility
2. Enter Sol’s production facility
3. Sabotage Sol’s production facility & Kill production line guards
4. Sabotage Sol’s production facility & Hack Sol’s production line
5. Sabotage Sol’s production facility & Open synth processor
6. Sabotage Sol’s production facility & Damage processing systems
7. Meet Zadra
8. Find main network terminal
9. Kill network terminal guards
10. Shoot armored door
11. Find way past armored door
12. Reach sealed wing
13. Clear lab
14. Dispense Locust sample
15. Remove armor from door
16. Return to Zadra
17. Reach airship
18. Kill armored brute
19. Reach airship
20. Get to Outbounders HQ
21. Find Rush
22. Help Rush
23. Reach fast travel station
24. Remove debris
25. Stop Sol’s Locust attack & Enter airship
26. Stop Sol’s Locust attack & Eject thermal capacitors
27. Stop Sol’s Locust attack & Destroy critical systems
28. Abandon ship

Starting Location: One Fell Swoop

Reach Sol’s production facility

Follow the quest marker to reach the facility.

Enter Sol’s production facility

When you reach the big gate, wait for it to open. Three bigger enemies will come out, you can run past them.

Sabotage Sol’s production facility & Kill production line guards

Follow the path inside the facility and get through another door. Here, kill all enemies to proceed.

Sabotage Sol’s production facility & Hack Sol’s production line

After killing the enemies, interact with the console near the golden barricade to open it.

Sabotage Sol’s production facility & Open synth processor

Now go through the open barricade and follow the path. You will reach the processor soon after, now interact with it.

Sabotage Sol’s production facility & Damage processing systems

While some enemies spawn, you can shoot the core of the processor to destroy it.

Meet Zadra

After destroying the processor, get back to Zadra.

Find main network terminal

Press the button next to Zadra, then follow her.

Kill network terminal guards

In the next room, kill all enemies to proceed.

Shoot armored door

After killing the enemies, shoot at the door.

Find way past armored door

Use your grappling hook to pull yourself up into the vent.

Reach sealed wing

Walk through the vent and drop into the lab.

Clear lab

Kill all enemies inside the lab.

Dispense Locust sample

Now interact with the terminal in the middle of the room.

Remove armor from door

To remove the armor, grab the canister with  /   / ‘V’ (PC) from the terminal and throw it onto the door.

Return to Zadra

Now get back to Zandra.

Reach airship

Now follow the marker. To open the door, grab a canister near the door on the left side, then throw it at the door.

Kill armored brute

Follow the path and you will find an armored brute. To remove his armor, you have to grab a canister from the middle of the room and throw it at him.

Then you can shoot the brute.

Reach airship

After killing the brute, follow the quest marker and climb up the ladder.

After climbing the ladder, you will soon reach a seemingly dead end. You can pull yourself up with the grappling hook on the right side.

Shortly after, you will reach the rooftop, pull yourself up with the grappling hook to reach the airship.

Get to Outbounders HQ

Now go back to the Outbounders HQ, you can not fast travel to that location.

Find Rush

Rush is in the middle of the area.

Help Rush

You have to kill all enemies to help Rush.

Reach fast travel station

Enter the Slime’s Five shop and drop down the ladder to reach the station.

Remove debris

Press  /  to remove the debris from the station.

Stop Sol’s Locust attack & Enter airship

Head back to the plaza outside and go into the yellow beam to enter the airship.

Stop Sol’s Locust attack & Eject thermal capacitors

Press the button inside the airship.

Stop Sol’s Locust attack & Destroy critical systems

Now shoot at all three systems to destroy them.

Abandon ship

After destroying the systems, a 30-second timer will start. You need to jump out of the airship.

This finishes One Fell Swoop in Borderlands 4.

NEXT: Rush the Gate

For all other Quests refer to our complete Borderlands 4 Walkthrough.