Sugapuff,
Hello, and I hope you're doing well!
I have two 3DS game consoles. (One is red; the other is blue.)
I have four 3DS game cartridges of "Animal Crossing: New Leaf." (I am playing three active towns and using the fourth for personal cycling.)
The physical cartridge matters for you directly playing "Animal Crossing: New Leaf." The individual 3DS game consoles render your Friend Code—and there is a need that you don't mix them up should exchange that information with another player whom you are hosting or visiting.
Candy83