Behold--! The Foundations of Eternity -- the intertwining of energies which is the basis of all that is! 
The Foundations of Eternity is an alternate plane of existence which serves as the basis of reality.[1] It is from there that every event in every universe originates.[2]
History
After acquiring the Beyonder's power, Doctor Doom showed the Foundations of Eternity to the Molecule Man, giving him insight into the intricate simplicity of existence as a gift. Doom then proceeded to remove a mental block the Molecule Man had, thus ending the power limitation he imposed upon himself.[1]
When Deadpool inadvertently interfered with the Beyonder's attempt to reclaim his power from Doom, both of them ended up going to the Foundation of Reality. Trapped in there, the Beyonder convinced Deadpool to release him in exchange for granting a wish of his. Consequently, the duo returned to Battleworld and Doom lost the power he had stolen. The Beyonder later granted Deadpool his wish, which was to resurrect Zsaji and return her to her home planet.[2]