The next entry in the Call of Duty series is rumored to be codenamed "Slipstream." That's according to @Helba_The_AI, who runs blizztrack.com, a site that tracks updates and uploads to Activision Blizzard's storefront, Battle.net.

Helba shared on Twitter that there is what appears to be files related to Call of Duty 2021 that have been uploaded to Battle.net, alongside logos with the name "Slipstream." While Activision Blizzard did confirm that the next Call of Duty is in development with Sledgehammer Games leading, the game has not been officially revealed or given a release date. Sledgehammer assisted with the development of Modern Warfare and Black Ops Cold War and led development on WWII. The next Call of Duty will also integrate with the Warzone, the free-to-play battle royale.

Helba also tweeted that the next Call of Duty may have an alpha coming soon, based on some text found in Battle.net's files. Earlier this year it was reported that the next Call of Duty game will be titled Vanguard and would take place during World War II. While the Vanguard title may be the official name of the game, the Slipstream title could possibly be used to secretly test the game or to avoid the official name of the game from being leaked.