How to Get the Oscar Mike Assault Rifle – Borderlands 4 Guide

In Borderlands 4, one of the most exhilarating aspects of the game continues to be the thrill of hunting for legendary weapons. Among the dozens of rare and powerful guns scattered across the galaxy, few are as sought-after as the Oscar Mike Assault Rifle — a weapon that perfectly embodies the chaotic, explosive nature of Borderlands 4 Items. Fast, loud, and devastatingly effective in the right hands, the Oscar Mike is the kind of rifle that can turn a tough boss battle into a fireworks show.

But this weapon isn’t easy to come by. Its drop rate is rare, and its acquisition process requires both skill and persistence. Whether you’re a Vault Hunter exploring solo or teaming up with friends for endgame challenges, understanding how to get the Oscar Mike Assault Rifle will make your journey a lot smoother.

In this guide, we’ll cover everything you need to know about obtaining the Oscar Mike — including where to find it, how to maximize your drop chances, what makes it unique, and how to build your character around it.

What Is the Oscar Mike Assault Rifle?

Before you dive into the grind, it helps to understand what makes the Oscar Mike so special. The weapon is a legendary-tier assault rifle, manufactured by Dahl, and is known for its tactical precision combined with sheer destructive potential. Its name, “Oscar Mike,” is military slang for “On the Move,” and that’s exactly how the rifle plays — it’s designed for fast-paced, mobile combat.

The gun comes with multiple firing modes that switch between burst and full-auto, allowing flexibility depending on your combat situation. However, what truly sets the Oscar Mike apart is its unique combat buff system, which rewards aggressive and mobile gameplay.

Its special ability, called “Tactical Momentum,” grants stacking bonuses to movement speed, reload speed, and weapon damage whenever you sprint or slide for more than two seconds. The longer you keep moving, the stronger your damage potential becomes. This makes it a perfect fit for characters who rely on momentum, mobility, and run-and-gun tactics.

At higher levels, the Oscar Mike can melt through waves of enemies and even bosses with sustained fire — especially when combined with critical hit builds and elemental mods.

How to Get the Oscar Mike Assault Rifle

There are three main ways to get the Oscar Mike in Borderlands 4:

Farming its dedicated boss drop

Completing special missions and challenges

Obtaining it through random world drops or loot events

Each method has its advantages and downsides, but if you’re serious about securing the weapon, you’ll want to start with its dedicated source.

1. Farming the Dedicated Boss Drop

The Oscar Mike Assault Rifle has a dedicated drop source: Captain Briggs, a mid-level boss located in the Wasteland Outskirts region on the planet Ferraxis-9.

Captain Briggs is a heavily armored military officer from Dahl’s private army who went rogue after the company’s collapse. His arena, the Desert Command Base, is a fortified bunker with open areas for ranged combat — making it a perfect spot to test your aim and movement.

To reach Captain Briggs:

Travel to Ferraxis-9 via your fast travel station.

Head toward the Wasteland Outskirts waypoint.

Follow the path north until you reach the Command Base Entrance.

You’ll face waves of Dahl deserters before Briggs appears as the final encounter.

Captain Briggs is a challenging boss with three main attack phases. During his second and third phases, he uses orbital drone bombardments and auto-turrets to pressure you, so keep moving to avoid being cornered.

Once defeated, Captain Briggs has about a 10% chance to drop the Oscar Mike Assault Rifle on standard difficulty. On Mayhem Mode or Chaos Level 3 and above, that rate increases to roughly 15-20%, depending on your loot modifiers.

If you’re farming, it’s best to reset the encounter by fast traveling back to the main spawn point and re-entering the boss zone. Players typically report getting the Oscar Mike within 15–20 runs, though RNG can vary.

2. Completing the “On the Move” Side Mission

If you prefer questing over grinding bosses, there’s another way to earn the Oscar Mike — through the “On the Move” side mission, which is part of the mid-game content on Ferraxis-9.

You can unlock this quest after completing the main story mission “Breaking Dahl Lines.” Once unlocked, visit the NPC Sergeant Reza, located at the Ferraxis-9 Forward Outpost.

Reza will task you with retrieving encrypted Dahl data from three separate military checkpoints while avoiding detection from security drones. The mission emphasizes stealth and mobility, teaching you to move quickly and use cover — fitting for a weapon built around movement bonuses.

At the end of the mission, you’ll need to defeat a mini-boss named Lieutenant Vex, who uses a prototype version of the Oscar Mike. After defeating him and returning the data to Reza, you’ll receive a guaranteed Oscar Mike Assault Rifle as your reward.

This version is typically one or two levels below your current character level, but it can roll with unique elemental bonuses depending on your build progress. Completing this mission is the only guaranteed way to get the weapon without relying on RNG.

3. Random World Drops and Events

The Oscar Mike is also part of the general legendary loot pool in Borderlands 4. That means it can drop from any high-tier loot source, including chests, legendary enemies, or world bosses.

Your chances are much lower compared to farming Captain Briggs, but if you’re doing Chaos Dungeons or participating in seasonal events like the Crimson Harvest, keep an eye out — sometimes, the Oscar Mike appears in event-specific loot tables.

During the Vault Line Warfare Event, for example, players reported increased drop rates for all Dahl-manufactured weapons, making it an ideal time to grind. These events rotate throughout the year, so it’s worth checking the in-game calendar for the next one.

Best Builds and Classes for the Oscar Mike

The Oscar Mike’s greatest strength lies in its synergy with mobile and critical-oriented classes. If your playstyle revolves around fast movement, quick reloads, and chaining kills, this weapon will feel tailor-made for you.

Here are some ideal class pairings and build suggestions:

1. The Vanguard (Soldier Class)

The Vanguard’s “Combat Flow” skill tree enhances movement speed, reload time, and weapon handling — all of which amplify the Oscar Mike’s Tactical Momentum passive. By stacking sprint bonuses, you can maintain nearly 100% uptime on your movement-based damage buffs.

2. The Operative (Stealth Specialist)

If you use the Operative’s cloak or decoy abilities, the Oscar Mike becomes a stealth powerhouse. Fire a burst, reposition, and re-engage — your high mobility allows you to maintain Tactical Momentum constantly, keeping your damage multiplier active.

3. The Siren (Elemental Caster)

While not traditionally an assault rifle class, the Siren’s elemental focus pairs beautifully with Oscar Mike variants that have elemental modifiers. Fire versions deal consistent burn damage, while shock variants shred shields. Combining elemental ricochet effects with sustained fire creates an almost endless stream of damage.

4. The Bruiser (Heavy Gunner)

If you prefer a more aggressive, front-line approach, the Bruiser’s melee and explosive synergy make the Oscar Mike ideal for mid-range combat. Equip explosive ammo mods and pair them with the Bruiser’s “Adrenal Rush” passive for devastating results.

Oscar Mike Weapon Stats and Traits

The Oscar Mike’s base damage varies slightly depending on your level and modifiers, but it generally boasts the following characteristics:

High base accuracy and stability, even during full-auto fire.

Two firing modes: 3-round burst and full-auto.

Tactical Momentum passive: movement-based damage stacking (up to 25% per stack).

Medium magazine size (36–45 rounds) with fast reload speed.

Optional elemental variants: Fire, Shock, and Corrosive.

Some rare Oscar Mike rolls include additional crit bonuses or ammo regeneration when sprinting, making them even more valuable for sustained combat.

Tips for Efficient Farming

Getting your hands on a legendary can be a grind, so here are a few ways to make the process faster and more efficient:

Use Mayhem or Chaos Mode: Higher difficulty increases legendary drop rates significantly.

Equip Loot Boost Artifacts: Items like the Treasure Hunter’s Charm improve the odds of dropping legendaries.

Play in Co-Op Mode: More enemies mean more loot opportunities per run.

Reset the Boss Quickly: Fast travel out and back into the area instead of restarting the game.

Keep Inventory Space Clear: Legendary drops can despawn if you’re over-encumbered.

If you’re running with a team, have one player focus on aggro while others handle weak points — this keeps the fight efficient and reduces time between runs.

Final Thoughts

The Oscar Mike Assault Rifle stands as one of the most versatile and exciting weapons in Borderlands 4. It rewards players who stay on the move, constantly adapting to the chaos of battle. Whether you earn it through Captain Briggs’ boss fight, complete the “On the Move” mission, or stumble upon it during a lucky loot run, this weapon becomes an instant staple in any Vault Hunter’s arsenal.

With its fast fire rate, mobility buffs, and ability to buy Borderlands 4 Weapons with nearly every class, the Oscar Mike embodies what makes Borderlands combat so addictive — stylish movement, constant explosions, and the satisfying rhythm of mayhem.

So grab your rifle, keep moving, and let nothing stand in your way. Because with the Oscar Mike in hand, you’re not just on the move — you’re unstoppable.