Polargeist is a fantastic take on the Geometry Dash series that adds new jumping obstacles, such as the yellow jump rings and the second cube sequence.
As part of finding a secret coin, Polargeist reveals the location of the cyan gravity pad and the gravity portal. The only catch is that you won't be able to try them out until Dry Out or xStep. Keep your distance from the ceiling and stay clear of the hanging bricks. The coin can only be reached from above, since the bricks below it act as a protective barrier. At 63%, you'll find The Cube, the second hidden coin after collecting the initial batch (at 44%). You need to time your jumps carefully to avoid the above spikes so you can reach the concealed gravity pad at the 77% platform.