All of rares games were co developed with nintendo, this is why rare games had superior graphics. Nintendo worked closely with rare to help them utilise all the 64's processing power (much to the annoyence of other developers Ocean, EA etc.)
Nintendo produced ALL of rares games, in other entertainment industries the producer has exclusive control over the rights.
Remember Donkey kong racing on the game cube, it only exsisted as a screen shot on the back of the Game cube console box, what happened there?
09/10/2006
The Mushroom Kingdom