Overview
"Insert the batteries to activate the device" is an objective during the Gate to the Otherworld main quest in Chapter 4 of Crimson Desert. After activating the lock device underground, you return to the round plaza to insert four cube-shaped batteries into pillars surrounding a central device. This requires Axiom Force and Force Palm.
Battery Locations
The four batteries are cube-shaped objects sitting on the ground in front of their respective pillars in the round plaza. Each pillar has an opening where the cube fits. The pillars are marked with orange objective indicators on your minimap.
How to Insert Each Battery
Repeat this process for all four batteries:
Grab the cube. Hold L3 / Left Stick to activate Axiom Force. The cube will lift off the ground.
Push it toward the pillar. While holding the cube, press R2 / RT to push it in front of the pillar opening.
Punch it in. Release the cube by pressing L3 again, then immediately use Force Palm (R3 / Right Stick) to slam the battery into the pillar.
Each successfully inserted battery fires a power beam toward the device in the center of the plaza.
Extracting the Unstable Core
After all four batteries are inserted, a cutscene plays. When it ends, target the blue orb floating in the center of the device. Hold L3 to activate Axiom Force on the orb, then hold L2 / LT while pushing the Right Stick upward for several seconds. This slowly extracts the unstable core from the device.
Next Step: Tenebrum
With the core extracted, the next objective is to approach and subdue Tenebrum. See the How to Defeat Tenebrum guide for the boss fight strategy.