Did you know you can couch co-op the 3DS Mario Party games with just one copy? It's great! Those that don't have the cartridge still enjoy the full experience with no exceptions, it's fantastic! Nintendo did a great job there. I'm not sure it is as appreciated as it should be. I play as much MP on the 3DS as I do on the consoles. I've really enjoyed 9 and 10 as well.