My #23, as guessed by TruckOSaurus, is Final Fantasy VII.
Originally slated for release on the SNES, Final Fantasy VII was pushed back for release on N64. But when the storage space on the N64 cartridge was deemed insufficient, developer Square decided to release the game on Sony's Playstation. Thus began a decade of Sony exclusivity for Final Fantasy, and a decade of decline for Nintendo -- although the two are only tangentially related. So Final Fantasy VII had a big impact on the industry, but it had an ever larger impact on public perception of RPGs. It wouldn't be an exaggeration to claim that FFVII was the first mainstream RPG -- it has sold 10 million copies, the most of any Final Fantasy game -- and was one of the first games to place a huge emphasis on story and production values. In fact, the game cost $45 million, the most expensive game of its time, and required a team of roughly 120 artists and programmers. It's not the best Final Fantasy game, but it's certainly the most influential.
