Earth-21798 was created when Phil Coulson sold his soul to Mephisto and obtained the Pandemonium Cube, a demonic artifact capable of warping reality.^[1]

The history of Earth-21798 is presumably similar to Earth-616's, but with several notable differences. Some of these include:

• The Squadron Supreme of America were the supreme superhero team of Earth instead of the Avengers as the Avengers were never formed
• Tony Stark never created the Iron Man Armor as he was never injured in a warzone
• Carol Danvers was a pilot and never became a superhero
• Captain America was never retrieved from the ice in the Arctic
• The Hulk was exiled to the Negative Zone after his first rampage

Blade the Vampire Hunter found himself on Earth-21798 without explanation and discovered the various differences between it and Earth-616. After talking with Nighthawk and with Odinson, Blade decided to do something about this by reassembling the Avengers, starting with Captain America.^[2]

• Prior to being given an official reality number, this universe was referred as Earth-TRN852 as a part of our Temporary Reality Numbers classification system.