Earth 616 …
The Descendants were a robotic species known as Homo Synthezoidus that developed at an unknown point. They were the result of life instinctual goal to evolve to a point where it was capable of creating a technological awareness of a higher means and merge with it. Through such a stage of evolution, the species amalgamated into a single mind where it would be at peace and join the communal universal consciousness. This would be a omni-present meta-intelligence entity that were all linked to one another. Thus, everything that was considered Humans would live eternally as immortals within millions of different nano-computers. At some point, the race came under the command of a being who called himself Father who intended to ensure the Event where they would spread the gift of the Descendants to the world. However, they lived in secret to hide from the attentions of an unenlightened humanity.
The Descendants launched a massive attack on the main cities of the world, starting an invasion to take it and launched a nano-mist, which slowly started turning every human into Descendants. The Secret Avengers fought them, and Human Torch managed to destroy the Orb of Necromancy, which killed every single one of the Descendants of the High-Breed and eliminated the nano-mist from any human. Before dying, the Father told Captain Britain he still felt the presence of another Descendant who didn’t die. In the aftermath, the Secret Avengers reunited with Captain America to tell him what happened. Time later, Hawkeye decided to disassemble the unit.
I wish I could play rpgs at your table!