Out of This World-SNES
Doshin the Giant-GC
I believe Cubivore and Doshin both broke 100k+ in Japan, but I don't think they did much elsewhere. Doshin wasn't even released in the US; still the only game I've ever imported. People know about OoTW, so it's not completely unknown, but I'd wager far more people do not know about it than those who do.
"I feel like I could take on the whole Empire myself."