2600 wrote:
I was curious what the likelihood that a game would require a certain revision of a mapper? i.e. requires MMC3B and won't work on any other revision
None for MMC3 that I know of. A few early famicom MMC1 titles need an A revision MMC1 but that's about it. I can think of "The Money Game" in particular. The earlier MMC1 revs do not support SRAM locking like the later ones do, and the game doesn't unlock the RAM.