From the Super Mario Wiki, the Mario encyclopedia
The player must play five rounds in which they match up the two systems to correctly align two halves of a banana as fast as possible. No penalty is given if the player makes an incorrect guess at any point, though at the cost of wasting time. The game ends once five rounds have passed.
The player must join the two Switches and slide their finger across both systems simultaneously, though this is never explained in-game.
"How fast can you clear five challenges?"
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