Developer Tribute Games and publisher Dotemu have announced the upcoming release of MARVEL Cosmic Invasion: The Siege of Castle Doom, a new premium DLC for the 1.5 million+ player tag-team co-op beat 'em up. The DLC will launch on Steam, Nintendo Switch, PlayStation 4 & 5, and Xbox Series X|S on November 10. In the Castle Doom mode, players must break through the defenses of Victor von Doom's foreboding stronghold before he's able to activate the Cosmic Inductor, a flawed weapon designed to thwart Annihilus but destined to end the cosmos as we know it. Each encounter survived will charge the Stabilizer, a genius creation of The Fantastic Four's Reed Richards that's capable of foiling his oldest nemesis' newest plan. Players can gather Battery Cells and complete challenges to earn defense, damage or tactical upgrades from a collection of 12 different perks, but failing challenges will debuff their fighters. The DLC also includes the debut of The Fantastic Four's Susan Storm as well as Doctor Doom as playable characters, new unlockable color palettes for all playable Super Heroes, and electrifying original musical tracks from renowned composer Tee Lopes. The Castle Doom mode's run-based action will challenge players to become an unstoppable powerhouse, with deadly Doom Bots allied with bosses returning from the base game to settle scores with them. The castle's forces grow in power as the ominous Siege Gauge fills, but players' heroic efforts will end instantly if the gauge completely fills before their climatic showdown. The DLC's celebration of MARVEL's golden eras also includes new equipment and events from Reed's Lab, as well as modifiers that can deepen the challenge and potential rewards available in future attempts. Players will need to choose their path through the castle's winding routes and thoughtfully select buffs to alter their combat abilities. The Castle Doom mode's thrillingly high-stakes challenge will be revealed in a new gameplay trailer today ahead of the DLC's launch.