Pokemon Yellow. Me and my incredible team of a Lv 89 Pikachu, Lv 100 Zapdos, Lv 33 Snorlax, Lv 48 Omastar, Lv 51 Butterfree and Lv 65 Nidoking finally got through the E4 after ~80 hours. If I recall correctly, it took me two hours to get out of the starting house in the first place. Still have the file, just holding on it's original cartridge.
I can't wait for it to come on the VC next month, I plan on running through with that same team of six and then not touching Pokemon again for a while (unless Gen VII looks irresistible.)







