An omnibus edition is like a big book that has all the books in a series put together into one. Think of it like a big sandwich with all your favorite fillings in it! Just like how you have to take smaller bites to eat a sandwich, you might have to take breaks when you read an omnibus because it's so big! But it's great because you don't have to keep going back to the library or bookstore to get the next book in the series. It's all right there in one big book!