Heat oven to 250° F.
Combine cereals, peanuts, pretzels and raisins in large bowl.
Combine melted butter, cocoa and sugar; stir into cereal mixture. Toss until ingredients are well coated.
Pour mixture into a greased 13x9x2-inch baking pan. Bake 1 hour, stirring every 15 minutes. Cool completely. Store in airtight container.
Servings: 10 cups