Invisible Bedrock

Invisible Bedrock is an invisible and indestructible block exclusive to the Pocket and Pi editions.

Obtaining
Invisible bedrock cannot be selected or broken using any tools, and is unobtainable without the use of external programs. When held in the inventory, it uses the stone texture.

Natural Generation
Invisible bedrock comprises the border wall surrounding old worlds. The wall does not generate past the height limit, allowing the player to walk atop it.

Usage
Invisible bedrock is transparent in rendering only, interacting with players and mobs as a solid block and blocking light. Any adjacent blocks are not rendered when viewed through invisible bedrock.