Overworld Void

Overworld Void is a type of Void that is located below the Overworld dimension, it is separated from the Overworld dimension by a bedrock layer. This dimension is unhabitable due to the emptiness here. Blocks cannot be placed here, if falling blocks enter the dimension, they will be deleted and destroyed instantly, the items from the block will also be destroyed.

There are no known entity that can survive the damage caused by this dimension. The size of the dimension is still unknown, but it's estimated to be 2^1024 blocks deep, or approximately 1.07×10^301 blocks deep. The dimension can deal damage and destroy any entity that enters the dimension almost instantly, making the dimension really dangerous (Ender Dragons can survive the Void's damage, but it's still unknown whether this is a bug or an actual ability given to the Ender Dragon).

Most of the time, the color of the dimension's 'sky' is cyan and black. Other colors can appear too, but they appear rarely, such as yellowish, and reddish. The color of the Overworld Void depends on the time on the actual Overworld dimension. In certain versions, the Void is cyan during daytime, reddish during sunrise and sunset, black during nighttime.

In some versions, there is a 'barrier' located 40 blocks below the bedrock layer. The barrier is invisible and cannot be broken. The only known way to pass through the barrier is by teleporting under it using commands and map editor. In some versions, you can ride a vehicle to survive the damage, this won't work in the other versions because the damage will be dealt in any y coordinate and there is also the Void Barrier.

Usually, mobs between 64 and 319 blocks below the bedrock layer of the Overworld will become completely black. They will also disappear instantly. Any (almost) entity that enters the Void will be deleted, including projectiles, animals, monsters, items, falling blocks, etc.

To enter the dimension, you will need to pass through the bedrock layer of the Overworld dimension which is physically impossible. But there are glitches that allows you to pass through the bedrock layer.