Best FL4K Builds (February 2020) – Mayhem 4 & Maliwan’s Blacksite

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

Our Borderlands 3 Best FL4K Builds features a look at some of the top options for the character class. We've got different builds that will be useful for Mayhem 4 and the Takedown at Maliwan's Blacksite! 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.

NEW: Mayhem 4 Grenade/Rakk Attack FL4K Build

Credit to Dakquan

Key Items: Unforgiven (Crit Hit Damage), Hunter-Seeker Grenade (Main Damage Dealer)

If you're tired of doing a lot of aiming and firing weapons, then this might be the FL4K build for you! This one focuses on hurling Hunter-Seeker Grenades that have the capability of critical hitting and using the damage bonus from the Unforgiven pistol. The build is fairly easy to use! Hurl your grenades at any enemy, and use Rakk Attack over and over. This deals a ton of damage, especially when combined with a good Unforgiven. You'll want to look for either the Rakk Attack!, Life Steal, or Elemental Damage Anointment for your pistol. R4kk P4k will be the Class Mod you look to use, it synergizes well with the build, but you mainly want to find one that gives additional weapon critical damage to Jakobs.

You can utilize a bunch of other weaponry in your additional slots, but overall they aren't required. The Nukem is a strong option, as well as an Electric Cutsman for tearing down shields. Overall, this build can be run pretty cheaply because you mainly just require those two particular key items.

As always, be sure to check out the video below to get a more detailed explanation on the build.

NEW: Mayhem 4 Radiation FL4K Build

Credit to Joltzdude139

The Radiation FL4K build is still a viable option in Mayhem 4! You are going to want to make sure you have the Red Suit Shield, because it grants you immunity to Radiation damage. That's a pretty big key, because you'll be splashing Radiation damage around, and even inflicting it upon yourself. The reason you want to do that is because you will also require an Elemental Projector Artifact which will give you a significant damage boost while you are suffering from an elemental effect of that type. The Devils Foursum is one of the weapons you want so that you can splash yourself with Radiation and gain that damage buff from the artifact. One of the other weapons you'll really want is a high damage Radiation Protuberance. This is a purple rarity weapon, so make sure to keep an eye out for it while you are farming.

In addition to those weapons and items, you'll likely want to run an ION CANNON which is great for picking yourself up when you get downed! A Red Fang Class Mod will also come in handy, because enemies will focus on your pet rather than you!

Be sure to check out the video below to get a detailed run through on the build.

Mayhem 4 Maliwan Takedown FL4k Solo Build

Credit to Dakquan

If you're looking to attempt Maliwan Takedown in Mayhem 4 by yourself, then this is the FL4K build to take with you! The build itself is fairly straight-forward in terms of skills, it's a lot of the stuff you've seen before with FL4K Fade Away crit builds. Itemization is a lot more important when heading into Mayhem 4 and the new raid. You'll want a Brainstormer to take on the many enemies you'll be facing. This will rip up shields and chain lightning onto multiple nearby enemies and is the main weapon you'll be using. The Maggie is your main weapon for when you're looking to deal damage to a single target, and the Cutsman is another high damage option for bosses.

Now that Anointments with +50% Elemental Damage are available, you will want to be rocking all three different elements if possible. These do not stack, so make sure you don't overlap them with the same elements.

A lot more information on this build can be found in the following videos:

Wontan Kill

Full Build Guide & Maliwan Takedown Run

Mayhem 4 Rakk Attack Build

Credit to WiLLiSGaming

Item Requirements: One weapon with the Anointment: "Enemies damaged by Rakk Attack! take 100% increased damage for a short time."

This build centers around launching your Rakks at enemies for huge amounts of damage. The Rakks themselves will often just destroy whatever they touch, but if the target hasn't died you will get the 100% increased damage buff by having a weapon equipped with the Anointment mentioned above. This is obviously very helpful in boss fights. Other helpful items are both a Shield and a Grenade which have an Anointment that gives you a 50% bonus to damage on Action Skill End. The R4kk P4k Class Mod is another great addition to this build, it will split your Rakks into two more Rakks once the first one hits an enemy. That gives you a lot more damage and will tag additional enemies giving you an additional damage buff!

You can find the R4kk P4k Class Mod by farming the Tink of Cunning in Mayhem 4. It is the final boss of the Proving Grounds - Cunning at Ghostlight Beacon. You can find the mission that unlocks this area in The Splinterlands at Pandora.

Check out the video for additional information and gameplay:

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About the Author

Shaun aka 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.

More Borderlands 3 Character Builds

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  1. none of these work. ive tried all these builds and i still get owned cant even make it past the gate of maliwan and my damage against any normal npcs is useless

    1. i use to play cc build with lyuda and do mayhem 3 graveyard in less than 5 secs. What’s the point man, do you have good items to use each different build ?

  2. Does it matter what pet i use for the crit Hunter build or can I pick any of them?

    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.

    2. I’m pretty sure it doesn’t matter that much.

  3. Gamma burst is active**

  4. 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!

    1. You’ve got 49 points allocated above, but only 48 are available in game.

  5. 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.