Thanks in advance for any help!
Details on the differences between Tag 1 and Tag 2 Tekken Tag Tournament (USA)
: Save data is often region-locked (e.g., an NTSC-U save from North America cannot be used with a PAL version of the game).
Losing this data means replaying the game dozens of times just to re-unlock Unknown—a tedious grind even for veterans. This is why managing your should be a priority for any serious player.