Borderlands 4: Harlowe Flux Generator Build Guide

Learn how you can create an overpowered Harlowe build around the Flux Generator Action Skill in Borderlands 4.

Harlowe’s Flux Generator Action Skill belongs to the Cosmic Brilliance (Green) skill tree in Borderlands 4. With the right skills, Augment, and Capstone, you can create a broken Flux Generator build that uses the Action Skill’s buffs to wipe out hordes of enemies and end-game bosses in the blink of an eye. 

The build’s core mechanic adds Action Skill Damage to your weapon, which is guaranteed to land Critical Hits with investments in Cosmic Brilliance skills.

Pros and Cons of the Harlowe Flux Generator Build in Borderlands 4

Pros

• Incredibly high damage with flexibility in weapon type. 
• Buffs teammates. 
• No Legendary gear requirement. 

Cons

• High damage lasts only while the Action Skill is active. However, its cooldown can be sufficiently reduced to keep it active almost constantly. 
• The build starts to work after you have the Augment, Capstone, and the Excited State skill. 

Also Read: Borderlands 4: Which Vault Hunter Should You Pick

Borderlands 4 Harlowe Flux Generator Build Skill Tree Setup: Passives, Augment, and Capstone

Passives and Bonuses

Cosmic Brilliance (Green) Skill Tree 

• Momentum: 5
• Neutron Decay: 5
• Confirmative Reality: 2

Branch 1

• Decoherence: 5
• Latent Charge: 5
• Runaway Reaction: 1

Branch 2

• Gamma Ray Burst: 4
• Harlowe’s Certainty Principle: 1
• Critical Funding: 2

Branch 3

• Refraction: 5
• Excited State: 5
• Accretion: 2
• Distribution Function: 4

Augment

• Nuclear Winter 

Inside the Flux Generator’s radius, Harlowe and her allies deal bonus Cryo Damage. Upon leaving the Flux Generator’s radius, they instead deal bonus Radiation Damage for 12 seconds. Applying Cryo or Radiation status effects to an enemy Entangles them. 

The bonus damage you deal because of Nuclear Winter is considered Action Skill Damage, which benefits from bonuses provided by Excited State, the Group Study Capstone, and other similar skills. 

Capstone

• Group Study 

Replaces the AoE bubble of the Flux Generator with a buff to self and allies. It increases Gun Damage, Fire Rate, Action Skill Duration, Action Skill Cooldown, and Reload Speed. If you deal Action Skill damage, Excited State ensures that the next hit will be a critical hit. With Flux Generator constantly applied to you with Group Study, all your damage will be Action Skill Damage, ensuring that all your hits will be criticals. 

Best Weapon and Gear Loadout for Harlowe Flux Generator Build in Borderlands 4

Weapons

• Weapon Type: Pistol / Shotgun
• Manufacturer: Jacobs
• Alt Fire: Spread Launcher / Beam Tosser 
• Priority: Bullet ricochet, multiple projectiles, fast fire rate 

Also Read: Borderlands 4: Best Early Game Weapons and Shields

Class Mod

• Concurrence Skill 

Part of the Blue skill tree, Concurrence increases Action Skill Duration for every Entangled enemy, which is important to sustain Group Study and keep your damage output high. Try to find a Class Mod with Concurrence. Any other skills the Class Mod provides are a bonus.

Ordnance

No specific Ordnance is required for this build, as Excited State provides guaranteed Critical Hits. You can choose the most enjoyable Ordnance from your available gear. 

Repkit

Use a Repkit with any of the following bonuses, with AMP being the most important. 

• AMP
• Overshield 
• Leech
• Repkit Cooldown
• Action Skill Cooldown

Also Read: Borderlands 4: Best Harlowe Build Guide

Best Specialization Options for Harlowe Flux Generator Build in Borderlands 4

Prioritize the following Specializations to maximize the build’s potential. 

• Survivor 
• The Best Defense 
• Contamination
• One Shot, One Kill
• Riddle You This

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