While not free, Bungie has hosted limited-time events like the Open Beta (Server Slam) in early 2026, which allowed players to download the game for free to test the servers .
Searching for " Marathon " as a free PC download often leads to sites offering the original 1994 classic and its sequels, which have been made free and legal to download by the developer. However, the upcoming by Bungie is a premium extraction shooter that is not free-to-play . The Modern Marathon (2026) Marathon PC Download Free Torrent
The Shacknews reports an installation size of roughly 25.30 GB on Steam, requiring about 52 GB of total storage space . The Original Trilogy (Free Legal Downloads) While not free, Bungie has hosted limited-time events