Anniversaries/December 20
From Sega Retro
December 20 (add)
- 1985 - Satellite 7 is released for the Sega Master System in Japan.
- 1986 - Great Golf is released for the Sega Master System in Japan.
- 1987 - Phantasy Star and Opa Opa are released for the Sega Master System in Japan.
- 1990 - Crack Down and Darius II are released alongside the Mega Pad third party controller for the Sega Mega Drive in Japan.
- 1991 - Dahna Megami Tanjou, Double Dragon II: The Revenge, F1 Circus MD, Nakajima Satoru Kanshuu F1 Grand Prix, Nobunaga no Yabou: Bushou Fuuunroku, I Love Donald Duck: Guruzia Ou no Hihou, Task Force Harrier EX, and Undeadline are released for the Sega Mega Drive alongside Donald Duck no Lucky Dime for the Sega Game Gear and Earnest Evans and Wakusei Woodstock: Funky Horror Band for the Sega Mega-CD, all in Japan. Slaughter Sport is released for the Sega Mega Drive in North America.
- 1993 - Hi-Roller Battle and Rocket Coaster are released for the Sega Mega LD in Japan.
- 1994 - Tecmo Super Bowl II: Special Edition is released for the Sega Mega Drive alongside NBA Jam for the Sega Mega-CD in Japan.
- 1995 - Mahou Kishi Rayearth Visual Guide Book and Sega Rally Championship Competition Driving Guide, both books, are released alongside Virtua Fighter Soundtrack Vol. 1: Shinshou Hassei, a CD, in Japan.
- 1996 - Virtua Fighter 3 Act.1 and Virtua Fighter 3 Act.2, both books, are released alongside Airs Adventure, Aponasi Gals Olympos, Aquazone Option Disc Series 1 Angel Fish, Aquazone Option Disc Series 2 Black Molly, Aquazone Option Disc Series 3 Blue Emperor, Aquazone Option Disc Series 4 Clown Loach, Aquazone Option Disc Series 5 False Rummy-Nose, Can Can Bunny Premiere 2, DX Nippon Tokkyuu Ryokou Game, Eisei Meijin II, m: Kimi o Tsutaete, NIGHTRUTH: Explanation of the paranormal - "Maria", Nissan Presents Over Drivin' GT-R, Ryougae Puzzle Game Moudjiya, Shining the Holy Ark, Street Racer Extra, Ultraman: Hikari no Kyojin Densetsu, and Virtual Kyoutei for the Sega Saturn in Japan. VR Golf '97, Andretti Racing, Blast Chamber, TNN Motor Sports HardCore 4x4, Tempest 2000, and VR Soccer are released for the Sega Saturn in North America.
- 1997 - Falcom Classics Chou Kouryaku Guide and Sega Touring Car Championship Hisshou Kouryaku Hou, both books, are released alongside Dragon's Dream for the Sega Saturn in Japan.
- 1998 - Shenmue/Shenhua, a CD, is released in Japan.
- 2000 - Jet Set Radio Original Sound Tracks and Sakura Taisen: Gouka Kenran Hikari Rokuonkan, both CDs, are released in Japan. Dino Crisis and Resident Evil 3: Nemesis are released for the Sega Dreamcast in Spain.
- 2001 - [[]] is released in Arcades for the Sega NAOMI board alongside Sakura Taisen Online and Yoshia no Oka de Nekoronde... for the Sega Dreamcast, Sonic Adventure 2: Battle for the Nintendo Gamecube, Sonic Advance for the Game Boy Advance, and GetBass and Phantasy Star Online Ver. 2 for Windows PCs, all in Japan.
- 2002 - Asobo! Yuki Gassen is released for J-Sky (50KB) compatible phones through Sega's Pocket Works portal in Japan. Pengo is released for J2ME compatible phones in North America.
- 2005 - The House of the Dead 4 is released in Arcades for the Sega RingEdge board alongside Dragon Book and Dragon Crystal for EZweb (BREW 2.1) compatible phones through Sega's Sonic Cafe portal in Japan. Sonic the Hedgehog Mobile is released for J2ME compatible phones in North America.
- 2007 - Football Manager 2008 is released for Windows PCs and Mac OS X in Japan.
- 2011 - Sonic the Hedgehog CD is released for the PlayStation 3 in North America.
- 2012 - Jet Set Radio and Sweets Tower: Okashina Eiffel Tou are released for iOS in Japan.
- 2013 - Happy Sonic! Live Wallpaper is released for Android devices in Japan, North America, and Europe.
- 2016 - Chain Chronicle: Akatsuki no Ryuusei, a book, is released in Japan.
- 2017 - Gunstar Heroes is made available for the Sega Forever service for Android devices in North America, Europe, and Australia and for iOS in North America and Europe.