Earth-8921 is a world that runs parallel to Earth-616 and has very much the same history. That world's Fantastic Four and Avengers were tricked into going into the past to collect slices of one of the Golden Apples of Idunn for the Asgardian warrior woman known as Knorda who sought the apples to regain her lost immortality, unaware that she was secretly being manipulated by Loki.  The spirits of the heroes were sent into various points in their pasts on Earth-616 to collect the slices. When Thor of Earth-8921 allowed the physical body of his Earth-616 Counterpart perish before his time, reality was changed, replacing Earth-616 with Earth-1000 where Knorda ruled the world.  Ultimately the heroes learned of Loki's hand in events and how he intended to take over and thwarted his plans, restoring reality to normal. 
This created a divergence in reality, on Earth-8921 Knorda pursued the slices of the Golden Apple, while on Earth-616 she accepted her mortality and died.
Knorda, Loki, Doctor Strange, Fantastic Four (Mister Fantastic, Invisible Woman, Human Torch, Thing), Avengers (Captain America, Thor, Vision, Iron Man, Scarlet Witch) Edwin Jarvis, Franklin Richards