Borderlands 3 is a game that's absolutely meant to be broken, and the best FL4K builds for solo and co-op play are excellent at doing that. There will obviously be some adjustments made as the game's lifespan lengthens and players begin to truly figure it out, but for the most part, every character has some extremely strong options that can absolute demolish all but the toughest bosses on the highest difficulties, and FL4K is no exception.

What is interesting about FL4K is that they are also the best at solo leveling to get to the point of the game where players can start finding groups and downing the toughest bosses. That's unique to the robot beastmaster - while every other character is perfectly serviceable at navigating the build-up to the Borderlands 3 end-game, none are as adept at it as FL4K and their pet builds. Because FL4K also has one of the best end-game builds currently available in Borderlands 3, that makes them the perfect choice for min-maxers looking for the smoothest experience possible from level one to Mayhem 3 True Vault Hunter Mode in Borderlands 3.

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Even better for players looking to use FL4K throughout the game and speed up their leveling process: Borderlands 3 is incredibly generous when it comes to respeccing character builds, so they won't actually lose much by having to swap builds once they arrive at bulkier boss content. Borderlands 3 may be receiving mixed reviews based on its extraneous game features - most notably its humor, which has been heavily criticized - its gameplay is still the satisfying loop of downing tough enemies, grabbing legendary loot, and moving on to the next one to repeat the cycle. Here's how to get there fast, and how to make quick work of big bosses.

Borderlands 3: Best FL4K Solo & Leveling Build

While all of FL4K's skill trees offer some quality options in terms of survivability, there is one specific build for the character that makes them nigh unkillable. Despite players still questioning the effectiveness of Rakk Attack, there's a build that gets healing from it, while simultaneously generating ammo through critical hit exploitation (something players should be doing anyways) and dealing cryo and fire elemental damage to utterly decimate most enemy types. If that sounds appealing, then read on for what is surely one of the most effective Borderlands 3 FL4K leveling builds in existence, based chiefly on the one developed here:

First, make sure FL4K's pet of choice is the Spiderant, then start with these 10 skill points in this order.

  • 3 Leave No Trace
  • 5 Interplanetary Stalker
  • 2 Head Count

This sets players up nicely for the early game, giving them bonuses to action skill cooldown and ammo refills while Interplanetary Stalker is a powerhouse in damage buffs against enemy types, especially when groups are unlucky enough to be varied. Also make sure to grab Rakk Attack! as an action skill here and augment it with Rakk Open a Cold One, which changes the action skill to deal cryo damage and can sometimes freeze enemies as a result.

  • 5 Two Fang
  • Spiderant Scorcher Evolution

This is one of the single most important gets in the entire build, and they're back-to-back. Two Fang is very powerful since it gives FL4K a 25% bonus to fire an additional projectile once it's maxed, making fast fire rate weapons deal a lot of extra damage. Spiderant Scorcher is the preferred evolutionary choice - it constantly regenerates FL4K's health and it can deal incendiary damage in an AoE burst randomly.

  • 3 The Most Dangerous Game
  • 2 Big Game

The Most Dangerous Game is a powerful option, one that allows players to get incredible bonuses for killing stronger-than-average enemies while also getting a reward bonus too. The extra cash flow isn't super important, but it helps. Big Game is a nice complement to this and keeps the Hunter skill tree going, since the Hunter skills are so powerful while active and it lengthens their time up. Here, players tend to diverge on what they want to do with FL4K to make leveling easier, but we've found that it's time to dip into a second tree in the form of the Stalker branch.

  • 1 Galactic Shadow
  • 1 Big Game
  • Equip Rakkcelerate over whatever non-Rakk Open a Cold One augment is active
  • 3 Furious Attack

Galactic Shadow is a no-brainer - it increases critical damage by 15% and causes FL4K to get less heat from enemies. Then, an extra point in Big Game helps round out that skill before players can jump into Furious Attack, another way to stack damage with FL4K.

  • 2 Furious Attack
  • 2 Eager to Impress
  • 1 Overlocked

This is all relatively straight forward passive stuff that increases FL4K's sustainability while also giving him a chance to trigger their bonuses more often.

  • 3 Overclocked
  • 1 Lick the Wounds
  • 1 Turn Tail and Run

At this point, players should equip Fade Away over Rakk Attack, and switch to two augments - Guerrillas in the Mist and Not My Circus. This will put all aggro on FL4K's pet and will also make Fade Away not end after the requisite three shots from FL4K at the cost of its duration. It's well worth it. Lick the Wounds allows FL4K's pet to revive them, while Turn Tail and Run helps increase survivability even more.

  • 2 Turn Tail and Run
  • 3 The Fast and the Furryous

These bonuses to gun damage and movement speed will help round out the trip into the Stalker branch. Next, players can finally finish up the Hunter tree...

  • 1 Megavore
  • 2 Eager to Impress
  • 2 Rage and Recover

This rounds out the last bit of the leveling build, which will also unlock Unblinking Eye, a strong replacement for Not My Circus. Unblinking Eye gives 225% extra critical damage, which makes Megavore even more appealing, since it offers players a 20% chance of getting a critical hit even without hitting the proper part on an enemy's body. This can be taken earlier, of course, but this leveling build assumes players will have the time and ability to hit criticals more often than not anyways.

Borderlands 3 FL4K Rakk Attack

Borderlands 3: Best FL4K Co-Op Build

Because this build will be end-game focused, we won't break down when and where to take each ability: just maximize these, courtesy of Forbes, and enjoy watching enemies disintegrate.

  • Furious Attack
  • Overclocked
  • Eager to Impress
  • Turn Tail and Run
  • The Fast and the Furryous
  • Interplanetary Stalker
  • Hunter's Eye
  • Two Fang
  • Big Game
  • Most Dangerous Game
  • Head Count
  • Galactic Shadow
  • Persistence Hunter

With this build, players will want to use the Gunslinger Jabber and focus on Fade Away as their action skill, since it will be the source of a lot of their critical damage. Active skills can be switched up, but Guerillas in the Mist and Unblinking Eye are certainly the two favorites, as they pile on the critical damage even more.

What this build does is use FL4K's Fade Away to get in close to an enemy with a high damage shotgun and blast them away with intense bursts of critical damage, thanks to bonuses to gun damage and reload speed as well. It generally melts all but the strongest enemies and in co-op play can just completely decimate bosses in short order. It's the type of build that genuinely might not be around forever - Borderlands 3 is a game that players constantly try to break but Gearbox is only so lenient about these sorts of builds. Enjoy it while it lasts and enjoy the neverending flow of loot that comes with it.

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