I finished the part of the battle where I needed to move a train cart across a room. I’m in a warehouse now where there are lights in the 4 corners of the room with a large room on the opposite side with a switch and connectors for 4 power cores. I can’t find any of them nearby though. What are you meant to do?
The 4 corners with the lights are the clues. One of these corners will have weird red things flowing around the metal pillars. Shoot these and they will vanish. Destroy them all and you will be able to access a compartment above that contains a core. Once you put the core into the main room, another light in a corner will have red things appear around it for you to go to to get the next power core.