Sidling down to the ceiling beams and slowly maneuver your way to the end. Near the end, look to the north and jump across ...

If you want to reach the main area of Abburey Quarry in Arknights: Endfield, you'll have to solve a couple of puzzles and open the main door.

Blue Gate Village Key in ARC Raiders unlocks a locked building with multiple loot containers that have a chance to spawn valuable items & blueprints.

Stella Montis Security Checkpoint Key in ARC Raiders unlocks a loot room in the Lobby that can contain some of the rarest blueprints in the game.

During the Park Way Party quest in the Originium Science Park area of Arknights: Endfield, you'll have to find and fix three generators for the door.