SEGA is a more recent producer for tri-Ace, where their first (and currently only) joint project is Resonance of Fate (known as End of Eternity in Japan). Prior to this arrangement tri-Ace have always used Square-Enix for publishing purposes.
SEGA were best known as a console developer starting in 1986 up until around 2000. Creating consoles such as the Sega Master System, Sega Game Gear, Sega Genesis (also known as the Mega Drive), Sega Saturn & Dreamcast.
After the Dreamcast however SEGA discontinued console production and moved on to be a third party software producer only, even in recent years working on joint projects with former rival Nintendo to create Sonic & Mario combined games.
In the RPG market Sega have produced several big name titles over the years, such as the Phantasy Star series & Shining series. While more recently Valkyria Chronicles and of course Resonance of Fate.
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