History
The Ark of History was built by the time-traveler Rama-Tut within Neverspace, a raging sea of paradoxes where broken timelines go to die. He intended the fortress to be his final resting place with safeguards placed to ensure only his bloodline could pass through its walls. However, it became a place of reunion between him and his future selves: the Scarlet Centurion, Kang the Conqueror and Immortus.
Immortus summoned his past selves at the Ark of History to task them with finding the pieces for The Prize. Having become aware of Immortus' plan, Mister Fantastic infiltrated the gathering posing as a new variant of Kang called Scion. When each of Immortus' variants traveled to different points of the Fantastic Four's history and slaughtered the heroes in the process of obtaining their respective piece of the Prize, Reed secretly intruded on each mission and saved one member of each incarnation of the Fantastic Four from their doom. After Immortus' younger selves returned to the Ark, Scion revealed his ruse and his true identity, and led the time-displaced Fantastic Four in defeating them. After the Time Variance Authority arrested the villains and reset the timelines where they had murdered the Fantastic Four, Reed returned to his present with all the pieces of the Prize.[1]