One-armed Robber: Complete Heist Guide

A practical guide to One-armed Robber, the free-to-play co-op heist game where every robber has exactly one arm: how heists work, stealth versus loud, the heist list, progression (levels, cash, skills, weapons), the new cosmetics system and team tactics.

Researched September 2026 — current as of the "Skins update patch" (September 14, 2026), following the Weapon Skins and Postal Office update (August 21, 2026). Live games change; check the linked sources if something differs.

What Kind of Game It Is

One-armed Robber (developer and publisher Duhndal, released December 15, 2023) is a chaotic first-person heist game, free to play on Steam with single-player and online co-op. You drive up in a truck, get into the building, reach the vault or target, stuff your duffel bag with loot and get out. The joke is the premise: you only have one arm, so everything you do (carrying, shooting, opening things) is a one-handed juggle. Bring a friend and you have two arms between you.

Quick Start

• You start with a suppressor and a lock pick. That's everything you need for a quiet first heist. Don't feel you have to buy anything before your first run.
• Start with Liberty Hawk Bank. It's the beginner heist: a small city bank without advanced security.
• Decide stealth or loud before you enter. Each heist supports both, but your loadout should match. Suppressor for stealth; damage and extended magazines for loud.
• Tie up civilians instead of shooting them. Killing civilians triggers a civilian casualty penalty that takes a cut of your total take at the end.
• Loot is the objective. Once in the vault, the goal is the same regardless of approach: fill the duffel bag, get it out alive.
• Your duffel bag has limits. If you can't fit all the vault loot, run back to the truck for a new bag or have teammates carry more.
• Levels unlock gear; cash buys it. Weapons unlock at a player level and then cost in-game money.
• Research skills. You pay cash to start a skill's research; it then progresses as you play. Each skill has three tiers.
• Use the server browser. Since January 2026, "Find game" opens a traditional server browser so you pick the session you join.
• Launch daily for crates. After 15 minutes of play, a cosmetic crate drops once per day when you complete a heist.

Core Mechanics

Stealth

• Guards patrol set routes. Watch a patrol before you move.
• Cameras can spot you. Destroying one is an option, but guards may come to check cameras that go dark (a January 2026 fix made guards reliably check destroyed cameras).
• Line of sight matters. The September 2026 patch tweaked some environment sightlines on the Postal Office specifically because guards could spot players unfairly.
• Lock picks open doors quietly; every new player starts with one.
• Powerboxes can be sabotaged; the Saboteur skill speeds this up.
• Lasers and alarms: Many vaults are protected by laser grids. Disabling them usually needs a password, a timer window or a panel (see each heist below).

Going loud

• Once the alarm is up, police respond and the heist becomes a firefight.
• Loud builds want damage and bullets: extended magazines, higher-capacity weapons and shotguns for close quarters.
• The Scavenger skill increases ammo from police drops, which is essential for long loud runs.
• C4 is an option for forcing entry, and the January 2025 update made C4 blasts physically throw NPCs.

Civilians

• Civilians can raise the alarm. Tie them up to neutralize them without penalty.
• Shooting them costs you money at the end through the civilian casualty penalty.

Loot and the truck

• Your duffel bag holds a limited amount. When it's full, carry it to the truck and grab a new one, or split the load across teammates.
• Plan the route from vault to truck before you start filling bags. The run back is where most loud heists go wrong.

The Heists

Heist | Complexity (our rating; only Liberty Hawk is officially called beginner) | Target and key mechanics

Liberty Hawk Bank | Beginner | Small city bank with no advanced security. Learn the basics here

Rodman Research Facility | Intermediate | Steal chemical beakers and process them in the lab centrifuge into a high-value chemical weapon

Lundenburg Liquors | Intermediate | Rare wine in the cellar, behind barred cells with a laser array; a security tag detector sets off the alarm if bottles leave the room

Black Diamond Casino | Advanced | Vault protected by two laser arrays that can only be switched off for 30 seconds at a time; a mobster basement guarded by a biometric hand scanner

Mansion Heist | Advanced | Steal a supercar from the basement garage during the owner's birthday party; laser grids, high-tech cameras, patrolling guards, guests, hackable security and multiple entry points

Harbour Heist | Advanced | Night-time thunderstorm at a shipping yard. Break into containers holding missile guidance chips; each has a laser grid you disable with a password, and opening one before disabling the alarm is punished

Postal Office | Intermediate | Sneak into a postal depot and break into delivery trucks full of jewellery using a password before they leave. Released as a free map in August 2026

Some maps are sold separately as in-game purchases (there is no Steam DLC page; the developer regularly runs "all maps 25% off" during Steam seasonal sales), while others have been released free; check the map select screen for what you own.

Heist-specific tips

• Lundenburg Liquors: Don't carry bottles out of the tagged room until the security tag detector is dealt with, or you'll trigger the alarm yourself.
• Black Diamond Casino: The 30-second laser window is the whole puzzle. Have everyone in position before someone flips the switch.
• Harbour Heist: Find the password first, disable the laser grid, and only then open the container.
• Postal Office: The September 2026 patch locked the shop doors (it's nighttime) and made important rooms more readable. Look for the truck password before breaking in.
• Mansion: Use the multiple entry points; the party guests are extra witnesses, so stealth here is about timing.

Progression

Levels, cash and weapons

Weapons unlock at a player level and are then bought with in-game money. From the January 2025 Weapons Update:

Weapon | Type | Unlock level | Price

MS950 | Shotgun (primary) | 12 | $475,000

SP5 | SMG (primary) | 15 | $525,000

UP99 | Fully automatic pistol (secondary) | 19 | $425,000

Sawed off | Shotgun (secondary) | 24 | $500,000

XN 1070 | Shotgun (primary) | 25 | $700,000

N1A | Semi-automatic rifle (primary) | 28 | $850,000

IM1-G | Assault rifle (primary) | 32 | $900,000

Other weapons exist (for example the SPR-12, which got a skins fix in September 2026), and attachments like suppressors, extended mags and red dot scopes customize each gun.

Skills

• Skills have their own tab in the main menu (its position has moved in recent updates).
• Research: Pay cash to start researching a skill. Research progresses as you play; when it completes, the skill unlocks and is equipped automatically.
• Tiers: Each skill has three tiers, each better than the last; finish one tier to research the next.
• You can research several at once, but your progress is split between them.
• Examples: Scavenger (more ammo from police drops) and Saboteur (faster powerbox sabotage).

Grenades (Harbour Heist update)

Grenade | Effect | Best for

Fragmentation | Explodes 3 seconds after the pin is pulled; don't try to pick it back up | Loud heists, clearing groups

Distraction | Lures a nearby guard to check it out for about 30 seconds | Stealth, moving a guard off a doorway

EMP | Disrupts nearby electronics for 30 seconds | Stealth, getting past electronic security

Cosmetics and crates (August 2026)

• Skins and charms can be applied to any weapon, and to several weapons at once.
• Crates drop once per day after 15 minutes of play when you finish a heist. They can also be bought and sold on the Steam Community Market.
• Opening a crate lets you pick a skin or charm and buy it with heist coins. Those skins/charms can't be traded or sold.
• A handful of skins are also buyable directly without a crate. Find them under Loadout, then Cosmetics under each weapon.

Team Tactics

• Assign roles: one lock pick/sabotage player, one lookout on guards and cameras, one or two on loot and bag carrying.
• Call patrols: In stealth, a single spotter watching a guard route saves the whole team.
• Chain bag runs: One player shuttles bags to the truck while others keep filling at the vault.
• Go loud together: If the alarm triggers, regroup rather than scattering. Police drops feed ammo to whoever has Scavenger.
• Share the grenades: Distraction and EMP are team tools; coordinate who throws them and when.

Common Mistakes to Avoid

• Shooting civilians and losing a chunk of your take.
• Opening Harbour containers before the alarm is disabled.
• Carrying tagged bottles out of the Lundenburg cellar too early.
• Buying a loud loadout and trying to stealth, or the reverse.
• Researching too many skills at once; progress is split.
• Overfilling the bag and not planning the truck route.
• Throwing a frag and trying to grab it back. Once the handle is off, it's going to explode.

Advanced Tips

• Stealth first, loud as a fallback. Most heists allow a switch to loud if stealth fails, so start quiet and keep a loud-capable secondary.
• Use EMP for timing puzzles like the Casino's lasers: it buys you extra seconds around electronics.
• Distract, then sneak. A distraction grenade moves a guard for about 30 seconds, long enough to cross a room.
• Farm cash on maps you know. A clean run on a heist you've learned beats a messy run on a new one when you need money for weapons.
• Check patch notes when a map changes. Recent patches changed sightlines and door states on the Postal Office.

FAQ

Is One-armed Robber free? Yes, it's free to play. Some maps are sold separately and are often discounted in Steam sales; cosmetics use heist coins.

Can I play solo? Yes. Single-player is supported, as is online co-op.

How do I find public games? Press "Find game" to open the server browser (added January 2026).

How do I get weapon skins? Launch daily and finish a heist after 15 minutes of play for a crate, then pick a skin or charm and buy it with heist coins. Some skins are purchasable directly.

What's the newest heist? The Postal Office (August 2026), followed by tweaks in the September 14, 2026 patch.

Why am I losing money at the end of a heist? Probably the civilian casualty penalty. Tie civilians up instead.

Sources

• One-armed Robber on Steam
• Steam news: Skins update patch (Sep 14, 2026), Weapon skins and free map (Aug 21, 2026), Server Browser (Jan 8, 2026), Harbour Heist (Dec 18, 2025), Weapons Update (Jan 3, 2025)
• Steam news API feed for One-armed Robber (heist, skills and penalty posts)