Arc Raiders is a game of strategy, survival, and hidden rewards-and few secrets are as coveted as the Hidden Bunker. Tucked away in the game's most dangerous maps, this underground facility holds high-tier loot, rare crafting ARC Raiders Materials, and progress toward weekly trials.

Opening it isn't a simple task, though. It requires timing, teamwork, and knowing how to navigate the game's dynamic map conditions. This guide breaks down every step to open the Hidden Bunker, from identifying when it's available to surviving the challenges that stand between you and its treasures.

First: Understand the Hidden Bunker's Availability

The Hidden Bunker isn't a permanent location you can visit anytime. It's tied to a special "Hidden Bunker" map condition that only activates on the Spaceport map (Accera Spaceport) for limited windows of time.

Before deploying, check the play menu for a glowing yellow "Hidden Bunker" tile. If it's greyed out, a countdown will show when the event will next go live. When active, the match duration extends from 30 to 40 minutes, giving you extra time to complete objectives and extract loot.

Note: The Hidden Bunker does not appear on any other map-only Spaceport. There's a separate secret bunker in Blue Gate, but it uses a different unlock process and isn't the focus of this guide.

Prep Your Loadout Before Deployment

Opening the Hidden Bunker is high-risk, high-reward. You'll face swarms of ARC enemies and competing raiders, so coming prepared is non-negotiable. Here's what every veteran raider brings:

Essential Gear

Ziplines: Most antennas (critical for unlocking the bunker) spawn on rooftops. A zipline lets you reach them quickly without wasting time climbing or fighting through ground-level enemies.

Heavy or Medium Weapons: ARC wasps and hornets spawn when you activate antennas. A crowd-control weapon will help you clear these swarms fast.

Medkits and Repair Tools: Healing options are limited inside the bunker. Pack extra medkits to survive fights with enemies and rival raiders.

Strong Armor: You'll take fire from both AI and other players. Don't skimp on protection-invest in armor that can withstand heavy damage.

Squad or Solo? Choose Wisely

While you can open the bunker solo, it's far easier with a squad. Teammates can cover you while you activate antennas, clear enemy swarms, and defend against rival raiders.

If you're going solo, prioritize speed and stealth. Avoid unnecessary fights, use cover to sneak past enemies, and focus solely on activating the antennas as quickly as possible.

Step-by-Step: Activate the Four Antennas

The core of unlocking the Hidden Bunker is activating four rooftop antennas scattered across the Spaceport map. Progress is shared across the entire lobby-so even if other squads activate some antennas, you'll still benefit.

Step 1: Locate the Antennas

When the Hidden Bunker condition is active, four white antenna icons will appear on your map. They spawn one each to the north, south, east, and west of the map's center, but their exact rooftop locations change every match.

Common spawn points include the Departure Building, Rocket Assembly, Control Tower, and Shipping Warehouse. Keep an eye on your map to stay on track-marking an antenna icon will give you a in-game guide to its location.

Step 2: Activate Each Antenna (and Survive the Swarm)

Activating an antenna requires two interactions. First, interact with the terminal to "establish connection"-this triggers an alarm and spawns ARC wasps and hornets nearby.

Clear the enemy swarm before proceeding. If you move away or die during this step, the activation will reset, and you'll have to start over.

Once the enemies are defeated, interact with the antenna again to send the unlock signal. The antenna's icon will disappear from the map for the entire lobby, indicating it's active.

Step 3: Repeat for All Four Antennas

Move quickly between antennas, but don't rush blindly. The western approach to the bunker is exposed, so use cover to avoid third-party ambushes as soon as any antenna is activated.

If you encounter rival raiders, decide whether to fight or flee. Remember-progress is shared, so you don't need to activate all four antennas yourself. Focus on staying alive first.

Find the Bunker Entrance

Once all four antennas are activated, the game will broadcast a lobby-wide announcement: the Hidden Bunker is open. Now, you need to reach its entrance before other raiders beat you to the loot.

The bunker is located on the western outskirts of Spaceport, between the Fuel Processing and Fuel Lines areas, west of the Departure Building. There are multiple entrances, but one unmarked entrance sits directly southwest of the Departure Building if you prefer a quieter approach.

What to Do Inside the Hidden Bunker

The Hidden Bunker isn't just a loot room-it's a multi-room complex with two key objectives: gathering loot and downloading data for weekly trials.

Loot the Bunker

Scour the bunker for loot containers, which hold high-tier weapons, armor, and rare crafting materials like ARC alloys. These rewards are far better than standard raid loot, making the journey worth the risk.

Be quick-rival raiders will be hot on your heels. Grab what you can, but don't linger too long in one spot.

Download Data from Terminals

The bunker contains eight active data terminals, marked by a green light above them. Interact with each terminal to start a download, and stay close-moving too far away will cancel the process.

Each terminal grants 500 XP, and downloading from all eight gives you 4,000 XP total. This also counts toward weekly trial progression, helping you unlock seasonal rewards.

Survive and Extract

Opening the bunker is only half the battle. The facility is a hotbed for PVP fights, as rival raiders compete for the same loot and data terminals.

Stick to your squad, use grenades or mines to defend yourself in tight spaces, and always keep an eye on your surroundings. Listen for footsteps or gunfire to avoid ambushes.

Plan your extraction route before entering the bunker. Locate a nearby Raider's Hatch to escape quickly-this ensures you keep your hard-earned loot instead of losing it to enemies or the match timer.

Key Tips for Success

Antennas can be activated by any raider-don't waste time fighting over them. Focus on your own tasks and let others contribute to the lobby progress.

If you see buttons instead of antennas (a rare variant), coordinate with other raiders to press all four-this will also unlock the bunker door.

A "Spaceport Outskirts Bunker Key" can occasionally be found as loot. This key lets you open the bunker directly, skipping the antenna activation process.

Clear nearby ARC patrols before activating antennas. Bastions and bombers often guard antenna locations, making solo activation risky.

Final Thoughts

Opening the Hidden Bunker in Arc Raiders is a test of strategy, teamwork, and survival. It's not easy, but the rewards-high-tier loot, cheap ARCR Items, XP, and trial progress-make it one of the game's most rewarding activities.

Remember to check the map condition before deploying, prep your loadout, and stay alert for enemies and rival raiders. With a little planning and coordination, you'll unlock the bunker's secrets and walk away with the gear you need to dominate future raids.