Lost Precursor City

The  is a location in the Crystal Hollows where the Sapphire Crystal can be obtained. In order to claim it you must gather 6 Automaton Parts witch you randomly get form killing Automaton, then you need to give all 6 parts to Professor Robot for him to repair the giant. The 6 parts are Electron Transmitter, FTX 3070, Robotron Reflector, Superlite Motor, Control Switch, and the Synthetic Heart. After you give all 6 components to Professor Robot, the door next to him will open and the Sapphire Crystal will appear in the giant and you can claim it.