Marvel Two-In-One #50
Remembrance of Things Past!
When Reed Richards conducts another experiment on the Thing's mutations over the years, he comes to the conclusion that Ben's preferred state is that of the "rocky hide" thing. He shows Ben another serum he had hoped would change Ben back into human form but deduces that it would have only worked on Ben back during the earlier days of his mutation where his "Thing" form was more reptilian in nature as opposed to a rock-like material.
Thinking that he'd be better off if he wasn't the Thing, Ben takes the serum and uses Dr. Doom's time machine to travel back in time to the early days of the Fantastic Four. There, before the Fantastic Four set up shop in the Baxter Building, Ben finds his earlier self.
The embittered past incarnation attacks Ben, not believing that he is his counterpart from the future. After a lengthy battle between the two Things, Ben manages to knock out his past self. He administers the serum that Reed had created for him and the past-Ben changes back into human form. When Ben himself doesn't change to human form as well, he figures he just needs to return to the present.
Traveling through Dr. Doom's time machine once more, Ben arrives back in the present where he finds that he's still in his mutated form. When he tells Reed of his adventure, Reed explains to Ben that his past is immutable -- and instead of changing his own history, Ben created an alternate reality.
Recurring Characters
Thing-616, Thing-7940, Mister Fantastic-616, Mister Fantastic-7940
Continuity Notes
Reed mentions that he had lost his powers recently. Those powers began to fade in Fantastic Four #154 until he eventually lost them in Fantastic Four #178. He remained powerless until they were restored by Doctor Doom in Fantastic Four #197.
This is the first time it is acknowledged that the Thing's form continued to mutate from his original dinosaur-like hide first seen in Fantastic Four #1 to his trademark brick-like appearance that began appearing circa Fantastic Four #10.
Ben goes back in time to the point prior to the Fantastic Four moving into the Baxter Building which occurred circa Fantastic Four #3. Based on the Sliding Timescale of Earth-616 Ben traveled back in time roughly five years from the point of this story to the past.
Ben refers to the Time-Platform as belonging to Doctor Doom. The Fantastic Four confiscated Doom's time platform after their first encounter with him in Fantastic Four #5, however as explained in Fantastic Four Annual #11 that Reed had to return it before it caused a diplomatic incident, but was able to build a replica before doing so.
Reed postulates that Ben's venture back in time created a divergent reality. However, it is later discovered in Marvel Two-In-One #100 that Ben actually traveled to an alternate dimension.