Hi all. we just got a couple of 3ds's for christmas. Darren ( dad 40y) thomas (son 6y).
Im here to ask a few questions and work this thing out.

like why does mario kart ds keep thomas's name when I play it in my (darrens) 3ds..we are using the same cart.

that and a few more questions

Ask away, my good man. To answer your initial question, all data is saved on the cartridge itself, not the system. So even if you had two systems, the data would still be the same.

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