The file
One box, two bags: fruit-flavored Mario shapes on the left, berry-flavored Zelda shapes on the right, and a cardboard divider so the two never mixed. The box was designed to look like an NES console.
It lasted about a year, which was normal for Ralston's licensed cereals. Sealed boxes now sell for hundreds of dollars, mostly to people who ate it in 1988 and want to look at it again.
Sources: Wikipedia — Nintendo Cereal System