Marvel Cosmic Invasion: The Siege of Castle Doom will launch this fall on PC and consoles. The newly announced DLC adds a game mode and two playable characters, though their identities have not been revealed.
The title and first-look art put Doctor Doom at the center of the expansion. Marvel, publisher Dotemu and developer Tribute Games have not announced a specific release date or price.
Prepare to face the wrath of Doctor Doom in an all-new DLC featuring a brand-new game mode, and two additional playable characters!
— MARVEL Cosmic Invasion (@MARVELCosmicInv) August 17, 2026
MARVEL Cosmic Invasion: The Siege of Castle Doom launches this fall on PC and Consolesð¥ pic.twitter.com/pUUmIpbsjH
View the original Marvel Cosmic Invasion post on X.
Doctor Doom and Castle Doom in Marvel comics
Victor von Doom rules the fictional nation of Latveria and is one of the Fantastic Four's defining adversaries in Marvel comics. Castle Doom is his stronghold, which gives the DLC a clear setting without confirming that the game will adapt any particular comic-book storyline.
The second Marvel Cosmic Invasion expansion
The game's first paid DLC arrived in May with The Thing and Cyclops as playable heroes. That update also said another expansion with a new mode and more characters would follow in fall 2026. The Siege of Castle Doom announcement gives that second release its name and theme.
Marvel Cosmic Invasion is a side-scrolling action game built around tag-team combat. It launched in December 2025 for PC, PlayStation 4, PlayStation 5, Xbox Series X|S, Nintendo Switch and Nintendo Switch 2.
Sources: Marvel Cosmic Invasion on X, Marvel's game page and Marvel's May DLC update.
Image credit: Marvel / Dotemu / Tribute Games.