You see Mysterious Device
Location
Replica Dungeon (through the Energy Portal).
Notes
It is located in a small room. The north wall says: "You see a monument. This wall seems quite fragile." When you say "hi" it will respond: "Mysterious Device: Cannot comprehend.".
To pass the NPC and access the room, you have to say "PLNSTRDR". Part of the Opticording Sphere Quest.