The Void is a stage introduced in the Mysterious Seven Project and is based off the dimension seen in the Amazing World of Gumball episode "The Void".
Over the course of the world's history, whenever a person, object, invention, game, fashion style or other miscellanea that was a mistake to the world came into existence, it would be removed and erased from the real world and ends up in the Void. At least sometimes when a mistake is sent to the Void, they seem to be frozen in time like a paused video, but one can break them back out of it just by touch. The Void has TV static as its background or outer space, and the laws of physics are warped in the Void so that there is less gravity and the direction of gravity's pull twists and varies all around the place. The mistakes sent to the Void are left hovering or floating all around it.
Once a mistake is sent to the Void, all evidence that they ever existed is removed from the world - everyone's memory of the mistake is erased (unless a person wears a tinfoil hat), the mistake's image will all but vanish from any photos and pictures containing them, and where anything that belonged to the mistake (such as their school locker or their house) was located, the world will just fold up over them to hide and get rid of them. When the world folds up over evidence of a mistake's existence this way, it is possible for one to force the fold wide open to form a portal between the Void and the world. This portal will suck up anything that is near it, and it works both ways, but it will begin to shrink over time and eventually close back up to stop the mistakes in the Void from getting back into the world.
The Mysterious Seven Project
The Void is a unlockable stage in the Mysterious Seven Project, unlocked after playing as Gumball 40 times. Thhe stage consists of three platforms and would be considered a walk-off stage. The first platform, the high cliff, is the most dangerous spot as it's directly near two blast zones. The second platform, made up from a car and a floating island with a house on it is the flattest and probably most normal platform on the stage. The third platform, a upside down cloud, is slanted.
The gimmick of this stage is the stationary objects that appear frozen in time but are activated upon touch such as the geometric 3D shape or the floating items that get in the air. These just move out of your way for the most part.