NUCLEAR WINTER
HARLOWE THE GRAVITAR BUILD
Last updated on January 31st, 2026
NUCLEAR WINTER
Level 1 to 50
Radiation • Ricochet • Burst-damage
Check out our updated Borderlands 4 Harlowe Build Guide, with a clear progression route, skill recommendations and best gears!
This build turns Harlowe into a powerhouse that deals a ton of damage with Neutron Capture. By stacking certain attributes, Chroma Accelerator explosion can lead to massive gun damage that shreds both mobs and bosses. Certain gun choices also benefit from our ramping damage buffs, with Katagawa’s Revenge being the top choice.
HOW TO PLAY THIS BUILD
The core of this build is Neutron Capture, which makes your CHROMA Accelerator damage grant huge buffs to your guns. Fast-firing weapons take full advantage of this bonus, and ricochets from Jakobs guns or parts will help you clean up groups.
- Against mobs: Open with your CHROMA Accelerator and detonate it close to large clumps of enemies. Use high fire rate weapons to spread ricochets everywhere while the buff from Neutron Capture is active. Havinga Kill Spring is the key to surviving, as you’ll be doing a lot of overkill damage that gets converted to heals.
- Against bosses or strang enemies: Use your CHROMA Accelerator, and let it deal a bit of damage to the boss first before you blow it up. After detonating it, use a heavy-hitting gun like the Katagawa’s Revenge or Convergence to melt the boss while Neutron Capture is still up. If you have a Penetrator knife, make sure to use that at any point to guarantee more crits.
STRENGTHS
- Huge temporary gun damage buffs through Neutron Capture
- High fire rate and ricochets to clear enemies quickly and efficiently
- Flexible weapon choices with multiple top-tier legendary options
WEAKNESSES
- Requires farming specific weapons/licensed parts
- Ammo hungry due to fast fire rate
- Low survivability without Kill Spring
- Heavily dependent on CHROMA Accelerator
GEARS
Weapons: We’re looking for high fire rate guns, so Vladof is an ideal base. Jakobs-licensed parts that make your crits ricochet are great too. As for legendaries, consider one or more of the following :
- Katagawa’s Revenge: Top pick because of its Stormcloud effect, which can deal an extremely high amount of damage.
- Convergence: A great choice for mob clearing.
- Lucian’s Flank: Its crits will refill the gun’s magazine. Paired with its high fire rate, you’ll be shredding mobs with this.
- Aegon’s Dream – Another fast gun that will shred mobs with ease.
Repkit: Kill Spring will keep you alive by converting some of your excess damage into heals.
Ordnance: Any throwing knife with the Penetrator augment, which guarantees crits on every attack.
Class Mod: Skeptic is great for restoring action skill cooldown whenever you hit enemies with status effects. Driver can be decent against bosses, though Skeptic works fine in most cases.
Shield: The Super Soldier legendary adds fire rate and ammo regeneration, which can help boost your DPS.
Enhancement: Proficient Quintane. It grants extra ricochets and crit buffs, massively boosting clear speed.
SKILLS
In the red tree, we start off with Cyclotron and Bleeding Edge to speed up our fire rate and reload speed. After that, everything else we’re taking will be focused around increasing our radiation damage to buff Neutron Capture for peak damage.
We make this even stronger by dipping into the blue tree and taking more skills that increase our action skill’s damage. Unstable Ice-Otope is the standout choice here, as it adds an extra element on top of our radiation.
Skill Planner: Nuclear Winter build
LEVELING UP GUIDE
Action Skill: CHROMA Accelerator
Level 2 to 6: Cyclotron (5/5)
Gain fire rate.
– Faster DPS.
Level 7 to 11: Bleeding Edge (5/5)
Gain increased reload speed.- Just nice to have in general.
Neutron Capture (Augment)
Damage dealt by your action skill will be stored. After it explodes, all of the stored damage will add to your gun’s damage for a short duration.
– With this, our gun will deal a ton of damage whenever we activate CHROMA Accelerator.
Level 12 to 13: Elementary (2/5)
Increase your elemental and status effect damage.
– Slight damage boost and opens up the next node.
Level 14 to 16: Enriched (3/3)
Gain additional radiation damage.
– This further increases our DPS while Neutron Capture is active.
Level 17 to 21: Poisoned Sun (5/5)
Increases your radiation damage and irradiation chance.
– Make Neutron Capture’s effect even stronger.
Level 22 to 24: Chain Reactor (3/3)
You deal bonus radiation damage to entangled enemies.
– This also increases Neutron Capture’s effectiveness.
Level 25 to 26: Fissile Launcher (2/3)
Whenever you deal damage to an irradiated or entangled enemy, fire a radiation dart at another target.
– This gives us some bonus DPS against groups.
Level 27: Dirty Bomb (1/1)
Irradiating an enemy will create an explosion that deals irradiation damage.
– Even more damage on top of all our other sources.
Demon Core (Capstone)
Your Unstable Energy Pocket will now fire radiation darts at enemies as it travels. Enemies entangled by your action skill are also immediately irradiated.
– Huge DPS boost.
Level 28 to 32: Mechanical Brilliance (5/5)
Increases your skill damage whenever your action skill deals damage.
– Even more damage buffs.
Level 33 to 37: Make Extraordinary (5/5)
Buffs your critical hit chance with skills, and this is increased even more whenever you entangle enemies.
– Increased damage output with our action skill.
Level 38 to 42: Bright Future (5/5)
Increases your fire rate whenever you activate or re-trigger your actionskill.
– More fire rate means more damage.
Level 43: Ripple Effect
Kill Skill. Killing an entangled enemy will cause another target to get entangled.
Level 44: Negative Entropy (1/5)
Increases your gun handling.
– We’re only getting this to open the next row.
Level 45 to 47: Precision Engineering (3/3)
Gain increased citical hit damage.
– More damage, obviously.
Levels 48 to 50: Unstable Ice-otope (3/5)
Kill Skill. On kill, all damage sources will now deal bonus cryo damage for a short period of time.
– Adds even more elemental damage to our kit.