Plot: Nostalgia 1907 is a 1991 adventure video game developed and published by Sur de Wave. Originally released for the Sharp X68000, it was later ported to the FM Towns Marty, PC-9801, and Sega Mega CD. Wikipedia
Plot: A-Rank Thunder Tanjouhen is an adventure game released in 1993 on Mega-CD. The game was developed by Riot and released by Telenet. The game's cover art was created by Yasushi Nirasawa, in his position as a model-builder for Hobby Japan magazine. Wikipedia
Plot: The Third World War, released in Japan as The IIIrd World War, is a 1993 turn-based strategy game for the Mega-CD developed by Micronet. A Sega Genesis version was planned but never released. Wikipedia
Plot: Mansion of Hidden Souls, also called Tale of the Dream Mansion in Japan, is a point and click adventure video game released for the Sega CD, developed by System Sacom and published by Sega in Japan and by Vic Tokai in the United States. Wikipedia