[From the back of the box]:
"The Marathon saga will lead you through giant starships of human and alien design. You'll do battle in the vacuum of space, beneath alien seas, on the surface of distant planets and in the ruins of ancient civilizations. Before it's over, you'll fight your way through more than 80 vast environments of blazing combat, fiendish traps and encounters with exotic lifeforms as you struggle to survive and prevail.
And that's just the single-player game."
"In the three games; Marathon, Marathon 2: Durandal, Marathon Infinity, you are a lone security officer battling to survive and triumph over starships full of savage aliens of all kinds. In the first chapter you struggle to clear the starship Marathon from the lien incursion. In the second, you are the puppet of the rogue AI Durandal, as he explores a lost civilization. Finally, you must fight not only aliens but your own nightmares as the saga comes full circle."
Also includes the Definitive Map Collection (over 1000 single-player and network maps), the Marathon Scrapbook (a history of Marathon and of Bungie and their games), some Marathon Collectibles (stickers, beta versions, etc.) and Pathways Into Darkness.