Borderlands 3 FL4K Builds – End Game Crit, Solo, & Pet Builds

We're taking a look at some of the best builds for FL4K in Borderlands 3!

Our Borderlands 3 FL4K Builds Guide features a look at some of the top options for the character and class. We've got different builds for each of the Hunter, Master, and Stalker skill trees! If you're playing the game solo, FL4K is one of the best options for that due to his affinity for pets and ability to fade into the shadows. FL4K is also capable of huge amounts of damage by combining his stealth abilities with skills that increase and guarantee critical hits!

FL4K Builds

We're featuring multiple builds that you can choose from which take advantage of the different skill trees.

Radiation Fl4K: TVHM & Mayhem 3 Build

Credit to Tickle Me Pink

You will need some items to make this work, but once you've got them this build will melt face in True Vault Hunter Mode and Mayhem 3! The Hunter part of the build is fairly standard and just adds the damage plus the ability to critical hit any part of the enemy. The Master tree is where we get the Gamma Burst ability that will combine with our pet for the additional Radiation synergy.

Weapon wise you are going to want to look for a Pestilence and a Double Penetrating Laser-Sploder. You will want them both to have the Anointed Beastmaster buff that gives 65% bonus Radiation damage when Gamma Burst is activated. Lyuda got nerfed, but it's still good if you can find a Radiation version of it.

One item for sure you're going to want to have is the Red Suit shield. This gives 100% resistance Radiation which is going to be an issue when you're exploding things all over the place. You also would likely to be radiated so you carry that cloud of radiation which damages nearby enemies.

If you want to learn more about this build, make sure to check out the video below!

Endgame Boss Melter Build

Credit to Digfig

This is currently likely one of the best builds in the game for not only FL4K but overall. It melts bosses down insanely quick, especially when you are able to track down a couple of key weapons that will push this build over the top. What this build does is allows you to enter Fade Away and completely rip through a boss' health by spamming them down with high damage hits from your weapon. Basically, every shot you fire is a critical hit due to your action skill, and then this is increased by Megavore which will crit regardless of if you hit a weak point or not. The constant critical hits mean you will be frequently gaining ammo back into your magazine due to Leave No Trace. Ultimately, you are able to fire as much as you want as fast as you can without ever having to reload in most cases!

While Fade Away will initially not allow you to fire all you want, you can augment that with Guerrillas in the Mist to remove that issue. You further increase your ability to deal damage with Unblinking Eye, which will give you a huge boost to critical hit damage on successive hits.

While a lot of the weapons that were good with this build got nerfed, you can still use the Lyuda or Lucian's Call!

For more equipment tips, I recommend watching this video:

If you're leveling up still, you can run a Torgue Shotgun in Sticky mode to generate a similar effect on enemies. You deal some initial damage to the enemy, but once you reload it will completely destroy them due to the explosive pellets that should now be exploding. If you want to level into this build, I do recommend following the guide listed below because it's not so great leveling using the Fade Away ability. This build comes together towards the end game, you're better off running Rakk Attack as your action skill.

We've got a full leveling guide for a very similar build to this which you can find right here!

Rakk Attack Build

Credit to Galaxy Blackout

If you want to try something a bit different than the usual, then going with a Rakk Attack build is a great option. One of the keys we're looking for here is to grab ourselves a Bounty Hunter class mod because it makes it so Bosses are treated as Humans, Beasts, and Robotics. This pairs well with Hunter's Eye, which is also the skill we want the mod to increase.

The Butcher is a solid option weapon wise, and can help you heal back up after using our Attack Command due to the 30% lifesteal we get from it. You'll also be looking for a Lyuda, particularly one with the anointed Rakk Attack! buff (Enemies damaged by Rakk Attack! take 100% increased damage for a short time). Basically, the requirement when it comes to weapons for this build is that at least one of them needs to have that anointed bonus on it. Once you have that, you will want to find an artifact that buffs whatever elemental damage that weapon has on it.

Lot more information can be found in this video:

Joltzdude's Turret Build

Credit to Joltzdude139

This is kind of a critical hit build, but it's a bit different because it utilizes Turn Tail and Run. That ability encourages you stand still for bonus damage, hence the name "turret" build because you'll literally be standing like a turret. The equipped skills are pretty standard for a FL4K build, but we're not taking Leave No Trace and Hunter's Eye which are fairly standard.

You will need some particular item to make this build really work well. A Lucian's Call is needed to freeze your enemies. This gives you easy access to critical hits, because you can be right up close to the enemy and not take any damage. If you're hitting a ton of crits, you'll be able to take advantage of Head Count which will recharge your Fade Away ability really quickly. The Dictator and the Flakker are also very strong in this build, they shoot quickly and hit with a ton of pellets. If you have The Dictator, make sure to put it in bipod mode for extra hits!

Shield wise you're going to want the Brawler Ward because it gives you a huge buff to weapon damage when the shield is depleted. You will be up close to enemies frequently, so your shield is going to be broken. Artifact wise, you're really going to want to have a Knife Drain based item. This allows you to melee an enemy and pretty much instantly put you back to full health. This is makes it really hard for you to die.

More details on this build can be found in the following video:

About the Author

Evident is a lifelong gamer and creator of websites. He mostly focuses on shooters, but has been known to dabble in the occasional card game as well. You can find him binge watching TV shows in his downtime.

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    1. It doesn’t matter a whole lot but spiderant and jabber would be best. Spiderant for health regen and jabber for extra crit damage.

  1. For your pet build, I would recommend not getting dominance. It’s not really a useful skill at higher levels, primarily for bosses. I recommend going all the way down to the stalker list to get the double damage buff for you and your pet when your at full health.

    I would would also remove points from the “Go for the eyes” skill as your pet rarely does crits for this skill to be useful enough. I would set up the beast master skill as follows. (Granted you have the legendary mod Red Fang – Taunts all enemies while gamma burst isn’t active) +2 Ferocity, +2 eager to empress, + 1 he bites)

    Skills: Gamma Burst
    Passives: Atomic Aroma, Endurance
    Pet: Great Horned Skag
    + 5 ferocity
    + 3 Persistence hunter
    + 5 Frenzy
    +2 He bites
    +3 Who rescued who
    +1 Psycho head
    +1 Mutated Defenses
    +2 Pack tactics

    I recommend using Great horned Skag as they tend to attack more and provide damage and gun damage buffs. The eridium Skag ‘s singularity pull isn’t needed with the RED FANG mod on as it already taunts all enemies to the Skag. Believe me they will surround your pet.

    For the Stalker Tree

    +5 Furious attack
    +3 Sic em
    + 4 Eager to impress
    +1 Lick the wounds or extra point else where
    + 3 Turn tail and run
    + 3 Fast and furious
    + 5Hidden Machine
    + 2 Rage and recover
    + 1 The power inside

    With points all the way down to the power inside. With gamma Burst active, granted you are at full health will provide 50% damage for your pet for 15 seconds.

    The main job for the player in this build is to support your pet, and let it tank all enemies. The health regen your pet receives from you killing enemies or damaging them will help to keep your pet alive. Also with turn tail and run, shotties, pistols or snipers from afar will gain that extra damage buff by staying still instead of moving for health regen.

    This build has helped me play solo on TVHM on Mayhem 3. Bosses and badasses alike have been tainted by my pet with the Red Fang Mod on. This build is also good with a team, as your pet will tank all enemies and your team just focuses on killing. Good hunting!

  2. On the crit build.. i would ask why you would use the red creature instead of the green one the boost your crit ? Since the red only boos health regen and damage resistance if i’m not mistaken ?

    1. Simply because the 5% extra crit dmg don’t really matter that much, and the weakness of the build is the survivability, so dmg reduction and 1% health/sec really helps out quite a lot in comparison.