Shenmue I and II, I think.
I started Shenmue when it was released back in 1999, but didn't complete it until 2005 or so when I went back to it.
I bought Shenmue II for the Dreamcast while on a business trip in Scotland back in December 2001. After I finished Shenmue I bought a serial adapter for my DC VMU, converted my completed save with a hex editor so it could be compatible with the PAL Shenmue II version. Started that in 2005, then shelved it. Then when I got series with my backlog, around 2014, I picked Shenmue II back up and finished it. So for the two games, 15 years. 9 years between start and finish for Shenmue II alone.
It was all worth it in the end...
I started Shenmue when it was released back in 1999, but didn't complete it until 2005 or so when I went back to it.
I bought Shenmue II for the Dreamcast while on a business trip in Scotland back in December 2001. After I finished Shenmue I bought a serial adapter for my DC VMU, converted my completed save with a hex editor so it could be compatible with the PAL Shenmue II version. Started that in 2005, then shelved it. Then when I got series with my backlog, around 2014, I picked Shenmue II back up and finished it. So for the two games, 15 years. 9 years between start and finish for Shenmue II alone.
It was all worth it in the end...