Title screen.

Ōkōchi Gengorō Ikka (大河内源五郎一家, lit. “Ōkōchi Gengorō Family” or “Gengoichi Shimoda”) is an unreleased Nintendo 64 simulation game. During the N64 era, there was no information about this game being featured in magazines or other media, but it became generally known on April 12, 2007, when Game Tanteidan, a used retro game store in Nihonbashi, Osaka, introduced a prototype ROM of the game on its blog.