The best Vex builds in Borderlands 4: Siren guide

The cynical and sarcastic Vex is not what you'd expect from a Siren in Borderlands 4. Instead of the phase grasp playstyle we've traditionally seen, Vex is actually more like the Beastmaster himself—FL4K—from Borderlands 3. While this new direction makes the best Vex builds in Borderlands 4 harder to pin down, she's got a lot more versatility thanks to it.

Below, I'll go over three of the best Vex builds you can make at max level, one for each of her unique skill trees, as well as a levelling build, so you can make the most out of Borderlands 4's Siren. Of course, I'll also go over how these skills all come together with weapons, class mods, and other gear to reach their full potential.

Best Vex builds in Borderlands 4

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Just like the other Borderlands 4 characters, Vex has three distinct skill trees that bring something new to the table, including an associated unique action skill:

• Vexcalation: Master kill skills (even without killing enemies) and fire spectral blasts using the Incarnate action skill to focus solely on increasing Vex's power. You won't be using any minions in this build.
• The Fourth Seal: This skill tree focuses on Vex's reaper and spectre minions using the Dead Ringer action skill, similar to Zane's Double Agent tree from Borderlands 3. The idea is to make the most powerful summons for extra firepower, while also using them to further boost Vex's own offensive and defensive capabilities.
• Here Comes Trouble: Use Phase Phamiliar to summon your best bud Trouble to wreck face together, similar to FL4K's Beastmaster playstyle in Borderlands 3. With a focus on elemental damage and survivability, this tree is perfect if you're looking for a more laid-back approach, though it's certainly not as strong as the other two options.

Vex's trait is Phase Covenant: Vex is attuned to the elemental type of her current gun, converting all action skill and melee damage into that type (including kinetic damage).

Now onto three Vex builds, starting with what's generally her strongest setup, a Vexcalation/Incarnate infinite bleed build. I've listed the skills, augments, and captones in the order you'll want to pick them up, though remember that you can respec if you'd like to tweak things while levelling.

Vex build: Infinite Bleed

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• Primary skill tree: Vexcalation
• Action skill: Incarnate
• Favoured element: Kinetic
• Best skills for class mods: Undead Eye legendary class mod for points in Blood Shot, or Psion class mod for points primarily in Bloodletter
  • Bonus stats like status effect damage/chance and kinetic damage are useful
• Recommended items: Hot Slugger (legendary shotgun), Seventh Sense (legendary pistol), Bod (legendary shotgun), throwing knife with penetrator augment, Triple Bypass (legendary repkit), Undead Eye (legendary class mod)
• Firmware: Deadeye (3), High Calibre/Trickshot (2)
• Specialisations: Riddle You This, In The Zone, One Shot One Kill, Contamination

You'd have to be living under a rock to not know about Vex's infinite bleed build, which is capable of shredding max-level bosses with just a single shot. This largely comes down to massive bleed status effect ticks (based on your gun damage) and using a throwing knife with the penetrator augment (AKA a crit knife) to cause bleed to trigger itself indefinitely.

The important thing to note about this build is that, while action skill duration and cooldown are crucial, since Incarnate buffs a bunch of stats, you won't actually be slinging out any Eldritch Blasts. Simply put, it doesn't deal as much damage as your gun will, so why waste time?

The most important skills in this build come right away, with Leeching Attunement, Bloodletter, and Material Components. These massively increase kinetic weapon damage and let you cause bleed, a kinetic status effect. Plus, you'll also have plenty of lifesteal and bonus reload speed. When paired with Essence Leech and Blood Is Power from the bottom right of the Vexcalation tree, you'll deal even more bonus kinetic damage based on your lifesteal, so it's a win-win.

You'll also want to jump over to the Phase Phamiliar tree to grab Enchantment, which provides additional bonus kinetic damage while your action skill is active. Likewise, Portents of Suffering from the Dead Ringer tree increases status effect damage, which includes bleed, while Cold Iron buffs gun damage.

This is where the Grave Harvest augment and the Grave Quickening skill from the Dead Ringer tree come into play. The main reason to pick Grave Harvest is to extend the duration of Incarnate by collecting soul orbs whenever you kill an enemy, though it also gives this build some AoE damage. If you're looking for more of a boss-nuking build, then Energy Vampire is the way to go. Grave Quickening, on the other hand, simply increases action skill cooldown rate after a kill.

Here's where you should spend your skill points:

Vex build: Summoner

• Primary skill tree: The Fourth Seal
• Action skill: Dead Ringer
• Favoured element: Incendiary (though you want multiple elements to spawn a variety of attuned minions)
• Best skills for class mods: Illusionist or Alchemist, the latter for points in Keen Suffering, Portents of Suffering, and Prismatic Ichor
  • Bonus stats like status effect damage/chance and action skill cooldown/damage are ideal
• Recommended items: Hot Slugger (legendary shotgun), Hellfire (legendary SMG), Firewerks (legendary shield), Illusionist (legendary class mod)
• Firmware: Deadeye (3), GOOJFC (2)
• Specialisations: Riddle You This, I Am A Gun, A Honed Mind, Contamination

This build centres around summoning multiple minions using the Dead Ringer action skill to boost Vex's damage output, while also benefiting from passive damage from the summons themselves.

The goal is to constantly have multiple minions on the field at once—gun-wielding spectres and scythe-slashing reapers—to deal bonus damage and apply status effects. Cold Iron and Fell Inscriptions boost gun and melee damage (plus max health) respectively, for both you and your minions. Obedient Fiends and Ancient Rites, meanwhile, provide blanket increases to minion damage.

Taking advantage of the Blood Sacrifice perk to trigger Kill Skills whenever a minion dies, you'll want to pick up just about every Kill Skill she has, particularly Grave Fiends and Grave Quickening. A point in Sanguine Fiends and Grave Assault is also handy, just since they'll be active so often.

This build also has a light focus on status effects, too, since your minions are attuned to your element. Portents of Suffering simply boosts status effect damage, while Prismatic Ichor makes it so that triggering a status applies another random element. From there, Cursed Blade and Extra Cursed let you and your Reaper minions curse enemies with melee damage, causing them to take kinetic status effect damage; Burning Attunement increases status chance when attuned to incendiary; the Wither augment deals status effect damage and causes enemies to take increased damage for a duration afterwards.

Here's where you should spend your skill points:

This build, in particular, has room for a few strong variations depending on where you'd like to focus. The build above uses both spectres and reapers to their full effect, though you could do one of the following:

• Swap the Hellish Harvest augment with Coven, and solely use reapers to buff your own crit chance.
• Swap the Dark Pact capstone with Heirloom to give your spectres a copy of your gun and use the Coven augment for a gun-summoner build.
• Remove 13 points across Prismatic Ichor, Recurrence, Fell Inscriptions, and Grave Assault and put them in the following Incarnate perks for a more gun/bleed-focused build:
  • Leeching Attunement (1/5)
  • Grave Sights (4/5)
  • Bloodletter (4/5)
  • Grave Implements (1/5)
  • Material Components (3/5)

Vex build: Here Comes Trouble

• Primary skill tree: Here Comes Trouble
• Action skill: Phase Phamiliar
• Favoured element: Cryo
• Best skills for class mods: Weaver class mod for points in Corporeal, Blood Is Magic, and Grave Thirst
  • Bonus stats like status effect damage/chance, action skill damage, and ordnance are valuable
• Recommended items: Any heavy ordnance weapon, Hot Slugger (legendary shotgun), Hellfire (legendary SMG), Firewerks (legendary shield)
• Firmware: Deadeye (3), GOOJFC (2)
• Specialisations: Tripwire, Full Spectrum Arsenal, Fragmentation Payload, Riddle You This

Do you find comfort in having a buddy by your side? Did you like FL4K, the Beastmaster, from Borderlands 3? Then this is the build for you, focusing on Vex's phase friend, Trouble, a cute (and deadly) spectral cat. While it's perfect for mobbing, since this build has some self-buffing potential even without Kill Skills, it should hold its own against bosses, too. I will warn you, though, Trouble's AI isn't too great, and this skill tree is significantly less potent right now compared to the other two options.

This is an ordnance build, first and foremost, with a focus on cryo damage, which'll also benefit Trouble because of Vex's attunement trait. Icy Attunement restores ordnance cooldown on kills while attuned to cryo, Claw and Bang boosts melee and ordnance damage for you and Trouble, and Blasted Fiends increases Vex's ordnance damage—a portion of which is also given to Trouble as minion damage. Trouble will also partially deal ordnance damage thanks to the Violent Outburst augment and Trouble Bubble capstone.

However, there's also quite a bit of survivability in this build, mainly with frequent overshields. The Overprotective Kill Skill grants both you and Trouble an overshield, while Blast Rites gives you an overshield and increased fire rate after activating your ordnance. These synergise with Corporeal to increase your damage dealt while you have an overshield, while also increasing maximum overshield capacity and duration.

Here's where you should spend your skill points:

If you'd rather not focus on ordnance damage, it's as simple as swapping from the Trouble Bubble branch to either of the other two. The Beast Mode augment and Unsealed capstone work well for its shock-focused branch, while Vorpal Fang and Double Trouble's branch is built around critical hits.

Nevertheless, I'd focus on getting points in Incarnate's various Kill Skill perks at the top of the tree, and Dead Ringer's minion perks going forward, whether that's through class mod bonuses or additional skill points from future level cap increases. It's rather annoying that the pet skills are split pretty evenly between Phase Phamiliar and Dead Ringer, as right now, you won't have enough points to fully beef up Trouble.

Borderlands 4 Vex levelling build

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While Vex's infinite bleed build might be better in the endgame, at least right now, it's not the best for levelling since Incarnate can feel a little weak in the early hours. Instead, I'd recommend a minion-based Dead Ringer build, primarily using Spectres, to deal massive amounts of status effects.

By summoning Spectres and frequently swapping our active attunements, we'll trigger multiple different elemental status effects on enemies. This is important because it's also a counter to the increased elemental resistances of enemies on hard mode; by focusing on more than just one element, you can destroy flesh, shields, and armour with little extra effort. Plus, it's great for mobbing and bossing alike, since this build doesn't actually need kills to activate Kill Skills (thanks, Blood Sacrifice).

The best part is that you don't really need any specific gear for this setup, though I would recommend farming for a handful of legendary gear every ten or so levels. This includes:

• Firewerks shield from Splashzone in the Riptide Grotto, Coastal Bonescapes, in Fadefields.
• Aegon's Dream assault rifle from Horace in Horace's Oversight, Hungering Plains, in Fadefields.
• Hellwalker shotgun from Saddleback and Immortal Boneface bosses in The Old Scrape dig site in Cuspid Climb, Terminus Range.
• Avatar class mod from Primordial Guardian Inceptus in the Fadefields vault, Arch of Inceptus. You'll need to find the vault key fragment locations to unlock this boss.

Other than these, just keep an eye out for Jakobs and Maliwan weapons, and either a Fire Dancer, Naturalist, or Psion class mod.

Here's how the levelling process looks for this Vex build:

Levels 2-6:

1. Starting in the Dead Ringer tree, put five points into Cold Iron to increase the gun damage of both you and your minions.
2. Activate the Coven augment for bonus health regeneration and critical hit chance on Reaper and Spectre spawns, respectively.

Levels 7-11:

3. Spend three points on Grave Assault to increase the DPS of you and your minions after a kill.
4. Spend two points on Portents of Suffering for additional status effect damage, which can also be triggered by minions. Remember to take advantage of Vex's unique attunement passive to counter elemental resistances.
5. With a few points under your belt, now's the time I'd recommend farming Splashzone for a Firewerks shield, as it's a great help early on.

Levels 12-16:

6. Put one point into Blood Sacrifice to trigger Kill Skills whenever a minion dies. This gives us easy stacks of Grave Assault and our next skill, Grave Quickening.
7. Sink four points into Grave Quickening for bonus action skill cooldown rate after a kill (or by triggering Blood Sacrifice with a minion death). This helps maintain more minions active on the field at any given time.
8. Now is a good time to farm for a new legendary weapon, like Aegon's Dream from the main story boss Horace.

Levels 17-21:

9. Spend five points on Prismatic Weaponry. This causes you and your minions to deal random bonus elemental damage with critical hits, which can even trigger status effects. This damage increases for each active attunement, so you're encouraged to swap elements regularly to summon different types of spectres.
10. You've likely unlocked the Arch of Inceptus vault in the Fadefields by now, so you can farm for the really powerful Avatar class mod.

Levels 22-26:

11. Put five points into Obedient Fiends to improve minion damage and minion skill damage.
12. Activate the Dark Pact capstone to gain an extra augment slot. You can also activate Dark Pact to heal and buff your minions for a short duration, extending the amount of time they'll be active.
13. Activate the Wither augment to allow Spectres to cast Wither on an enemy on spawn, or when you activate the Kill Skill. Wither deals status effect damage and also increases the damage the affected target takes for a duration.

Levels 27-32:

14. Pick up Diener for one skill point to gain an additional charge of Dead Ringer.
15. Spend five points to max out Prismatic Ichor, causing you to apply another random status effect when you or your minions trigger a status. This is guaranteed to activate after Spectres use Wither, let alone from elemental damage done by you or your minions' standard attacks.

Levels 33-36:

16. Put three more points in Portents of Suffering for even more status effect damage.
17. Put a final point in Grave Quickening to help with minion uptime.

Levels 37-41:

18. Move over to the Vexcalation skill tree and put five points in Leeching Attunement. This gives you some much-needed survivability from lifesteal, as well as bonus DPS through a faster reload speed while you're attuned to kinetic damage.

Levels 42-46:

19. Put five points in Bloodletter in the Vexcalation tree to give gun and minion critical hits a high chance to cause bleed, a kinetic status effect. This will be boosted by the status effect traits from previous points in the Dead Ringer tree.

Levels 47-50:

20. Return to the Dead Ringer tree and put three points in Keen Suffering to give status effect damage a chance to critically hit. With standard status effects, Wither, and bleed all piled up, this is a significant damage boost with only two points.
21. Spend your final point on Burning Attunement, mainly to gain increased critical hit damage, alongside status effect chance, while you're attuned to fire. Since these effects persist for a duration after swapping attunements, just like Leeching Attunement, you'll benefit from an even bigger boost from Prismatic Weaponry.

From here, I'd recommend either staying with this build and farming for better legendary gear in the endgame, like the Rainbow Vomit, class mods, and enhancements, or respeccing fully into an Incarnate bleed build. It all comes down to your approach, though I'd still veer away from the Phase Phamiliar's Trouble playstyle in the endgame.

Once you're finished with this Vex levelling build, your skill tree should end up looking like this:

Other builds

These builds may not take the top spot for their respective skill tree or playstyle, but they're still fantastic and fun to play, so we've archived them for you here. For now, we've brought back our Witchy Trigger Finger build with some new improvements.

Vex build: Witchy Trigger Finger

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• Primary skill tree: Vexcalation
• Action skill: Incarnate
• Favoured element: Kinetic
• Best skills for class mods: Undead Eye legendary class mod for points in Blood Shot
  • Bonus stats like status effect damage and kinetic damage are handy
• Recommended items: Finnity XXX-L (legendary sniper), Undead Eye (legendary class mod), Quicksilver (legendary enhancement), Bod (legendary shotgun), Triple Bypass (legendary repkit), Timekeeper's New Shield (legendary shield)
• Firmware: Heating Up (3), Bullets To Spare (2)
• Specialisations: The Best Defence, Riddle You This, In The Zone, Now With Caffeine

While an infinite bleed build is the winning ticket for Vex right now, it will no doubt be nerfed (or fixed, depending on how you look at it) very soon, and that's where Witchy Trigger Finger comes in—my preferred build before everything was overshadowed by the crit knife's broken bleed potential.

This build is all about using high critical hit chance to deal kinetic bleed damage (which is also considered a status effect) and trigger Kill Skills without killing enemies. While it's still great for mobbing, you'll see just how bonkers it really is against bosses.

The key difference between this and an infinite bleed build is that, firstly, this isn't abusing any unintended interactions, and it's quite reliant on gear. You'll need Vex's Undead Eye legendary class mod, Finnity XXX-L's economical overheating, the Quicksilver enhancement, and the Heating Up firmware to guarantee the critical hits necessary to activate the class mod's bonus Blood Shot almost constantly. The Bod is also a great pick for this build (since it's technically a sniper), and I can't help but love the Wombo Combo.

To kick things off, you'll want to pick up Grave Sights, Grave Implements, and Material Components. Together, these perks give you bonus gun, crit, and kinetic damage (including kinetic status effects, AKA bleed). You could also swap Material Components for Fiendish Invigoration to get bonus movement speed and fire rate after using your repkit, which is key to this build anyhow.

Then, you'll want Grave Power to increase the max stack of Kill Skills, and Mortal Terror to trigger Grave Sights, Grave Implements, and other Kill Skills with critical hits. With our gear choices leading to a high crit chance, you'll max out these Kill Skills in no time.

The final focus of the build is specifically on bleed, using Blood is Power for bonus kinetic damage based on your lifesteal when your health is full, and Blood Shot, which is based on your current health when activated. When combined with Grave Vitality and Essence Leech, you'll maximise the returns of these skills. This is also where the Undead Eye class mod comes in, too, as you get bonus points into Blood Shot, and the ability to trigger it on sniper kills and critical hits.

While Incarnate's Eldritch Blast does very little damage in comparison to your guns in this build, it's necessary for a number of buffs. When using the Witchy Trigger Finger augment, dealing damage with Eldritch Blast or Phase Explosion significantly increases gun damage and reloads your current weapon. Essence Leech is also doubled while Incarnate is active. So, get the Vibe Check capstone to pair with Witchy Trigger Finger, and Grave Sustenance from the Phase Phamiliar tree to help keep Incarnate active for as long as possible.

Here's where you should spend your skill points:

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