no cable needed. but with a ds you can only play ds games with two or more people.
GBA games wont work in multiplayer.
highly recommended for DS muliplayer:
Mario kart
mario party
Castlevania (forgot which part)
Animal Crossing (can be fun)
New Super Mario Brothers and // or Mario 64 DS (the minigames on it are hilarious in bigger groups
these games you can get evrywhere, but there are a lot more playworthy ones!
these are for the start. be aware that you can play some games up to 16 players...but most of them are up to 4 players. and for some you only need one actual gamecartridge, the others can download the data from the host DS in the wi-fi network you created with it.
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PLEASE WAIT...BUILDING RAGE
DEM DAYS, WHEN EVERYTHING IS HIP HOP
"Beat the stage for an extra ending with monkeys"

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