Complex sentence: The cereal was an assortment of other Kellogg brand cereals alread in existence mixed together, commonly described as the result of cereals swept up off the Kellogg's factory floor.
Split into simpler sentences: The Cereal was an assortment of other kellogg brand cereals alread in existence mixed together. It was commonly described as being a all the cereals swept up off the Kellogg's factory floor.