Sega CD (thing)

This add-on to the Genesis was plagued by bad titles, mostly FMV, that gave it a horrible reputation. A few games were made that actually made good use of its capabilities:

• Ecco the Dolphin
• Earthworm Jim: Special Edition (added a level, weapons, and possibly the best ending ever in a video game)
• Eternal Champions: Challenge from the Dark Side
• Lunar: Eternal Blue and possible other RPGs (I'm not an RPG fan)