Inside 3 cthulhu phantom

Inside3 is a labyrinth hidden inside a cube. We play blind with the help of the plan engraved on the surface. This model cannot be dismantled, harder and with a coded plan. This model contains a second ball locked in a secret area (the Phantom) which complicates the task for the player by blurring the auditory cues. 13 models exist in total. Difficulty level of this model: 13/13