Do you mean Tick Tock Clock that you can play offline but not online, or do you mean something not in the game entirely? Because I have seen that you can play offline courses online very easily (all you need is Datel's Action Replay DS), but tracks not coded into the game is different. Is it possible to insert your own tracks by ripping apart the rom and inserting code? that would be cool, because then you could play with Custom tracks (which Mario Kart DS needs anyway)
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