The last adventure-style JRPG released for the Playstation was One Piece: Oceans of Dreams! from Bandai in May 2003. This was over two and a half years after the Playstation 2 had been released.
You might think a licensed game is an unremarkable swan song for the genre on the PS1, and you’d be right. However, this game’s story did, at least, have an impact on the One Piece franchise, as it was adapted as a filler arc for the anime in 2005.
If you want to go even later than that, there was a tactical RPG called Black/Matrix OO released on the PS1 by Flight-Plan a year later, in May 2004.
It was in fact the last original game released for the PS1 in Japan. Here’s some footage:
Other late additions to the PS1 JRPG library include Digimon World 3 in July 2002.
However, the last year for major new releases for the PS1 was 2000, a year that saw the release of Breath of Fire IV, Dragon Quest VII and Final Fantasy IX. Quite a year!
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