The Eggman Invasion is an event that appears in the Sonic the Hedgehog comic series and its spin-offs published by Archie Comics. It was a coup d'état that took place in the Kingdom of Acorn where the evil scientist Dr. Eggman took over the city of Mobotropolis, from which he launched his campaign to conquer the rest of Sonic's World. This would lead to his eventual conflict with Sonic the Hedgehog and the Freedom Fighters.
Dr. Eggman launched his coup following the a stand-off between the Kingdom of Acorn and the United Federation, which he instigated with help from Walter Naugus and Dr. Snively. The trio convinced King Acorn that the United Federation intended to invade the kingdom, forcing the king to act. Unfortunately, this left the kingdom vulnerable to Eggman's conquest, and he soon took over the kingdom and sent both the king and Naugus to the Special Zone. Westside Island then became the foothold from which he launched his efforts to unite all of Sonic's World under his banner as the Eggman Empire. However, his efforts also set the stage for his greatest opposition, as several children who were victims of the coup united under the leadership and inspiration of Sonic and became the primary resistance to Eggman's regime as the Freedom Fighters.
- Sonic Universe #72, "Spark of Life Part Two"
- Sonic Super Digest #12, "Sonic Comic Origins: The Traitor"
- Sonic/Mega Man Free Comic Book Day 2014, "Sonic Comic Origins: Sally--The Exiled Leader"
- Sonic the Hedgehog/Mega Man X Free Comic Book Day 2014, "Rotor–The Exiled Inventor"
- Sonic the Hedgehog #252, "At All Costs Part 2: A New Lease on Life"