Borderlands 4 One Fell Swoop Walkthrough
This comprehensive guide will help you complete the "One Fell Swoop" mission in Borderlands 4. Follow these steps to sabotage Sol's production facility, master the Locust sample mechanics, and stop the impending airship threat.
Mission Overview
- Mission Type: Story Mission
- Location: Sol's Production Facility → Outbounders HQ
- Recommended Level: 15-18
- Key Mechanics: Locust Samples, Environmental Destruction
One Fell Swoop Complete Walkthrough
Objective 1: Sabotage Sol's Production Facility
1
Talk to Zadra at her lab in Outbounders HQ to receive the mission. She'll provide you with essential information about Sol's operations.
2
Travel to Sol's production facility and eliminate all enemies at the entrance. Use cover as the area has multiple elevated positions with enemy snipers.
3
Further along the entrance, you'll find a large door tinted with green. Be cautious when approaching as it will open suddenly, revealing two aggressive Bulkheads.
4
After defeating the Bulkheads, enter the facility lobby and clear the subsequent areas filled with various enemy types. Watch for environmental hazards like steam vents and electrified panels.
5
As you progress further into the facility, you'll encounter a Bio-Bulkhead contained in a chamber. Access the terminal in front of the glass to hack it and release the creature against your enemies.
6
Advance to the next room and eliminate all enemies. Locate the synth processor at the center, open it, and carefully shoot the core through the gap to destroy it.
7
Return to the lobby and meet Zadra to take the elevator that will bring you to the next phase of the mission - stopping Sol's airship.
Pro Tip:
Before taking the elevator, make sure to loot all nearby areas for ammo and health, as you'll face significant resistance in the next section.
Objective 2: Stop Sol's Airship
1
Clear the area with Zadra. When she asks you to shoot the armored door (which will have no effect), look up and take the ventilation shaft. Inside, turn right, drop down, and break through the vent to enter the lab.
2
Clear the lab of enemies and approach the Locust sample dispenser to obtain an explosive sample. Throw it at the nearby armored door to destroy it.
The Locust sample mechanic is crucial for this mission - remember how to use it for the upcoming boss fight.
3
Return to Zadra and use another Locust sample to destroy a second armored door, gaining access to the airship docking area.
4
Slide down to reach the boss arena where you'll face the Bio-Bulkhead. Use the Locust dispensers in the area to obtain samples that will temporarily disable its armored skin, allowing you to deal damage.
Boss Strategy:
- Stay mobile to avoid its charge attacks
- Use the high ground for better aiming opportunities
- Time your Locust throws carefully - wait until its armor is fully visible
- Focus fire on its critical spots when armor is disabled
5
After defeating the Bio-Bulkhead, proceed to the airship. Unfortunately, you'll arrive too late to prevent its departure. Use the teleporter to return to The Howl and then to Outbounders HQ.
Objective 3: Stop Sol's Locust Attack
1
At Outbounders HQ, locate and assist Rush while avoiding corrosion damage from the ongoing Locust attack. Keep moving to avoid pools of corrosive material.
2
After bringing Rush to safety, proceed to the HQ bunker to reactivate the fast travel station. Use your grappling hook to remove the debris blocking access.
3
Exit the bunker and find a way to board the airship. Shortly, the airship will activate a tractor beam - position yourself within it to be lifted into the ship.
4
Inside the airship, locate the terminal to eject thermal capacitors. You don't need to eliminate all enemies - focus on the objective. Then, locate and destroy three critical systems scattered throughout the ship.
5
After destroying all three systems, immediately retreat through the hole you entered from. You have only 27 seconds to escape before the ship is destroyed.
Warning:
The escape timer is strict - don't linger to collect loot until after the mission completes and you can return to the area.
Completion Note:
After successfully escaping the airship, you'll complete the mission and receive your rewards. Return to Zadra for additional dialogue that sets up the next story mission.
One Fell Swoop Mission Rewards
Base Rewards
-
Cash: ~$15,000
-
XP: ~4,500
-
Eridium: 12-15
Equipment Reward
-
Sniper Rifle (Blue or Purple Rarity)
The specific stats and manufacturer vary based on your character level and playstyle.
Cosmetic Reward
An exclusive skin that applies a bio-mechanical pattern to your weapons.
Borderlands 4 One Fell Swoop Pro Tips
Combat Strategies
- Use corrosive weapons against mechanical enemies throughout the facility
