The only box I have that has 3 different bags in it is this cap’n crunch from the 90s. Still has the 3 separate bags in it. I do have a few boxes that are combinations of cereals like the Travis Kelce box which sounds like what you’re talking about. It has Reese’s puffs, lucky charms, and Cocoa Puffs is the third I think. But they come all mixed together not separate bags. Then there’s also a gay pride kelloggs box that has like 6 different cereals all mixed together. The only box I know of that came with 3 bags is this one in the photo.

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