This Sega Genesis game was a gem back in the 90s. It was an extremely good game and one of the easier games meant for kids. Back then there was no internet and I kept playing this with my sister, and now that there is internet around, I am quite surprise this game wants you to play it three times. One as Mickey himself solo, another as Donald alone, and the last been a co-op game using both characters. This run is a no damage run for co-op.
BTW, playing as Disney's mascot boy is over-rated. Usually the host would prefer to play as him and be player 1 but I rather spice things up instead and be unique.