Looking at Sega Marine Fishing (obviously yet another Naomi game). After some time of study I’ve found the way to bypass the annoying Naomi I/O fault (there’s a clear program flow RAM check at 0xc0279be).

Interestingly, it looks like that our renderer goes nuts with some elements of this (especially the “Rayman-style” Fishermen and presumably missing fog effect):




Source:mamedev.emulab.it/kale/