Arc Raiders is packed with hidden loot rooms, environmental puzzles, and points of interest scattered across its maps. Many of these puzzles are simple at first glance but include randomized elements that require awareness and a bit of ARC Raiders Coins searching. The Ancient Fort on the Blue Gate map is a perfect example. When you first approach this crumbling stronghold, you'll likely notice a locked cellar door and a handful of unpowered electrical boxes mounted around the structure. Solving this puzzle rewards you with a loot-filled underground chamber-but getting inside requires you to locate three batteries whose spawn points change every match.

This guide walks you through everything you need to know to open the cellar door at the Ancient Fort, including the exact locations of electrical boxes, common battery spawn points, and tips to speed up your search. Having enough ARCR Coins will also help you increase your speed.

Unlocking the Cellar Door at the Ancient Fort

The Ancient Fort looks unassuming at first-just another elevated defensive hold with a few rooms and vantage points. However, tucked along its exterior is a cellar door sealed tight with three indicator lights positioned above it. These lights directly reflect the status of the three electrical boxes you must power. If all three lights turn green, the door unlocks automatically.

Where to Find the Electrical Boxes

Unlike the batteries, the electrical boxes are always found in fixed locations. Your challenge isn't locating them-it's powering each one by slotting in a battery. Here's where to find the boxes:

Southern Exterior Wall

The first box is mounted directly on the outside of the southern wall. It's low to the ground and easily visible while circling the fort.

Inside the Tower (Upper Floor)

Enter the central tower structure and climb to the upper level. The second box is attached to the interior wall here.

Second Floor Interior Wall

Head to the upper interior walkway of the main fort building. You'll find the final box fixed against a wall on the second floor.

Once all boxes receive power, the cellar door lights turn green, and you'll hear an audible activation sound indicating the latch has released.

Battery Locations - All Known Spawn Points

The core challenge of this puzzle comes from the randomized battery spawns. Each match, three batteries appear somewhere in or around the fort-often in subtle or tucked-away spots-which means no two attempts will feel identical.

Fortunately, the Arc Raiders community has mapped out the most reliable spawn areas. While exact positions vary slightly, batteries tend to appear in predictable zones around the fort's perimeter and on certain elevated positions.

Below are the most common locations you should check:

1. Small Perimeter Structures

Around the fort are several minor buildings, tents, and supply sheds-these are the most consistent battery spawn spots. Walk around the entire outside perimeter and peek inside:

Wooden shacks

Small storage huts

Lean-to shelters

Crates and supply boxes near the walls

Batteries often blend in with clutter, so move slowly and scan thoroughly.

2. Ground-Level Corners and Exterior Walls

Many players overlook the simple spots: corners, shadows, and debris piles along the exterior walls. Batteries may spawn:

Against the lower edges of the fort walls

Near piles of rubble

Behind fencing and barricades

Do a full clockwise or counter-clockwise sweep around the fort to avoid missing any easy pickups.

3. Inside the Fort Interior

Although less common, some batteries appear inside the main interior hallways or rooms of the fort. Check:

Under staircases

Along the inner walls

Near scattered furniture or broken crates

Interior spawns often occur near the upper floors, so sweep upward levels if you come up empty outside.

4. The Top of the Ancient Fort

This is one of the most frequently overlooked-but highly reliable-battery spawn points.

Head to the very top of the fort's roof, where you'll find a wide platform with strong sightlines. Batteries occasionally spawn:

Near the central rooftop wall

Besides the roof-edge debris

Against railings or parapets

If you've located only two batteries and can't find the third, this elevated rooftop is the best place to double-check.

Completing the Puzzle

After collecting a battery, return to one of the three electrical boxes and insert it. There's no required order-you can power them in any sequence.

Once all three boxes are active:

All three lights above the cellar glow green.

A mechanical unlocking sound plays.

The cellar door swings open.

Climb down the ladder inside to reach a compact loot room. The rewards vary from modest to excellent depending on RNG, but this location is always worth a stop if you're already in the area.

Be aware: the noise of the door opening and the loot room can attract nearby players or hostile units, so keep your guard up. Other raiders might try to ARCR Coins for sale snag the Items you worked for.