From Sonic Retro
April 8 (
- 1994 — The build date of the "0408" Sonic the Hedgehog 3C prototype.
- 1998 — Issue #13 of the comic series Knuckles the Echidna is released in North America. Issue #127 of Sonic the Comic is released in the United Kingdom.
- 2006 — "Eye Spy", the 74th episode of Sonic X, airs in North America.
- 2008 — Amy no Page One is released for Club Air-Edge compatible phones though Sega's Puyo Puyo! Sega portal in Japan.
- 2009 — Face to Faith: Sonic and the Black Knight - Vocal Trax and Tales of Knighthood: Sonic and the Black Knight Original Soundtrax, both CDs, are released in Japan. Issue #199 of the Sonic the Hedgehog comic series by Archie Comics is released in North America.
- 2014 — Sonic Unleashed is made available for digital download on the PlayStation Store in North America.
- 2015 — Issue #271 of the Sonic the Hedgehog comic series by Archie Comics and Issue #6 of the Sonic Boom comic series are released in North America.
- 2016 — Mario & Sonic at the Rio 2016 Olympic Games is released for the Nintendo 3DS in Europe.
- 2017 — "Muckfoot", the 74th episode of Sonic Boom, airs in North America.
- 2020 — "Chika Keikoku no Himitsu", the 62nd episode of Sonic X, airs in Japan.
- 2022 — Sonic the Hedgehog 2: The Official Movie Novelization, a book, is released in North America. The Sonic the Hedgehog 2 film premieres in theaters in Japan and the United States.