> I've been running some of the 0.156 roms and noticed a lot of them were missing c69 > c70 c75.bin. > > Where did they go? Some new BIOS files?
Instead of adding per game, there were made devices and given their own shortname that is referenced by the game (like a bios) but doesn't need to be in the games' folder but in 'namcocxx' where xx is the number.
You can verify this by running the set you are questioning with -listcrc: 'mame tekken -listcrc' shows: 399faac7 c76.bin namcoc76 C76 (M37702)
A rom scanner/rebuilder such as clrmame would have already done this for you if you rebuilt from earlier roms.