At once? Then click the play button on the video above. But, be warned that this is ... well, it's weird.
Frankly, we don't understand why someone would do this. Sure, we want to hear every K.K. Slider song too, but we don't want to listen to them all at once.
[Via Go Nintendo]
Tough question for some, easy question for the DS Fanboy staff: it has to be K.K. Slider! Come on, people! Any other idea is lacking any kind of reasonable evidence to support it, in light of Slider's diligence to his job (he never misses a Saturday night show!) and his knack for 
