From Sonic Retro
June 22 (
- 2001 — Sonic Adventure 2 is released for the Sega Dreamcast in Portugal and the United Kingdom.
- 2003 — "Eggman Kichi Sou Kougeki! (Zenpen)", the 12th episode of Sonic X, airs in Japan.
- 2006 — Sonic the Hedgehog is released for EZweb (BREW 3.1) compatible phones through Sega's Sonic Cafe portal in Japan.
- 2011 — Sonic Adventure 2 Original Soundtrack 20th Anniversary Edition, a best-of compilation album, is released on CD in Japan.
- 2016 — Sonic the Hedgehog 25th Anniversary Selection, a compilation album, is released on CD in Japan. Worlds Unite Volume 1: Deadly Fusion, a trade paperback, is released in North America. Sonic the Hedgehog 25th Anniversary Selection is made available to download from Amazon and iTunes in North America and Europe.
- 2018 — "Mighty and Ray", the fourth episode of Sonic Mania Adventures, is released on YouTube.