Doom gets a castle, a countdown and — starting tomorrow — your evening. The Siege of Castle Doom, the new premium DLC for Marvel Cosmic Invasion, launches Tuesday, November 10, 2026, and it is not the usual extra-levels-and-done expansion. Developer Tribute Games and publisher Dotemu have rebuilt their 90s-style arcade brawler as a run-based assault on Castle Doom itself: pick a door, take the fight behind it, and reach Victor von Doom before the Siege Gauge runs out and he fires the Cosmic Inductor. It is a different shape of game wearing the same pixel-art gloves, and it lands tomorrow on Steam, PlayStation 4, PlayStation 5, Nintendo Switch, Nintendo Switch 2 and Xbox Series X|S. The base game is required. Of course it is.
That is the news. The interesting part is what the structure does to a brawler that was, until now, a straight line. Our base-game feature, “Marvel Cosmic Invasion — The Spirit of the 90s Arcade Brawlers Lives On,” made the case that the game’s charm is its directness: walk right, hit things, swap heroes with the Cosmic Swap tag system, repeat until the Annihilation Wave is a memory. Castle Doom keeps the hitting. It changes everything around the hitting.
Marvel Cosmic Invasion Becomes a Run-Based Siege
The premise is admirably blunt. Doom has a weapon — the Cosmic Inductor — and a timer. You have a castle full of his defenses and a Siege Gauge draining while you work. Instead of marching through a fixed sequence of stages, a run through Castle Doom asks you to choose your route door by door, deciding which fights to take and which risks are worth the clock. Every door is a small wager: a tougher room might pay out better, but the gauge does not care about your ambitions. It just drains.
This is the roguelite grammar — runs, routes, a clock, consequences — applied to a genre that traditionally runs on quarters and stubbornness. Whether it works will depend on the two things launch-eve trailers cannot prove: how varied the rooms feel on a fifth run, and whether the gauge creates tension or just homework. But on paper, it is the right experiment for this particular game. The base campaign’s strength was never its level structure; it was the moment-to-moment brawling and the tag-team combos. A mode that shuffles the rooms and lets the combat carry the variety is playing to the roster’s strengths, not papering over them.
It also gives the game something it previously lacked: a reason to run it back that is not simply a higher difficulty or a cleaner clear. A failed siege is not a wasted evening if the route taught you something. That is the pitch, anyway. Tomorrow we find out if the castle is as replayable as the pitch needs it to be.
Choose Your Door, Race the Gauge, Spend Your Perks
The connective tissue of a run is the upgrade system. Gathering Battery Cells and completing challenges during the assault earns upgrades drawn from a pool of 12 perks — the build-crafting layer that decides whether your Doom run is a cautious march or a glass cannon with good cardio. Twelve is not a huge pool, and that is probably deliberate. In a brawler, perks need to be readable at a glance in the middle of a screen full of aliens; a perk you have to pause and study is a perk that breaks the game Tribute actually made. Expect the choices to be broad and immediate rather than fiddly: more damage, better survivability, stronger swaps, the kind of decisions you can make in three seconds and feel for three rooms.
The door-by-door routing matters for the same reason. Cosmic Invasion supports up to four players with drop-in, drop-out co-op, and route choices in a co-op brawler are never just tactical — they are arguments. Somebody always wants the hard door. In solo play the route is a difficulty dial you set room by room; in co-op it is a negotiation conducted at arcade speed, with a draining gauge acting as the world’s most effective tiebreaker. There is a version of this mode that is merely fine. There is also a version — the one where the gauge is tuned tight enough that dithering is genuinely punished — that becomes the way people play this game from now on. Tuning is everything, and tuning is the one thing we cannot verify until the doors open.
A failed siege is not a wasted evening if the route taught you something. That is the pitch — tomorrow we find out if the castle is as replayable as the pitch needs it to be.
Doom and the Invisible Woman Join the Marvel Cosmic Invasion Roster
Two playable additions headline the character side, and one of them is the joke the whole expansion is built around: Doctor Doom himself joins the roster. You can storm Castle Doom as its owner, beating Doom as Doom, while — per the reveal coverage — Doom also narrates the heroes’ invasion of his own stronghold. Villains playable in their own boss content is an old arcade pleasure, and Tribute clearly knows it. Doom’s kit is the real question. A brawler lives or dies on whether a new character changes how a room plays, not just how it looks, and a character built around imperious ranged control would sit very differently in the roster than another pair of fists.
The second addition is the more mechanically interesting one on paper: Susan Storm, the Invisible Woman of the Fantastic Four. Force fields and invisibility are, in brawler terms, defensive and positional tools — shields for teammates, breathing room in a crowded room, a way to control space in a genre that usually only controls it by emptying it. In a mode built around a draining gauge and chosen fights, a character who can manage a room’s pressure rather than simply add to yours could quietly become the siege pick. Or she could be a novelty. Character balance in a 17-hero roster — the base game’s 15, plus these two — is not a promise anyone can keep from a trailer, and we are not going to pretend otherwise tonight.
What is not in doubt is the value of the additions for the mode itself. A run-based structure eats characters for breakfast: every new hero is a new way to route the castle, a new pair for the Cosmic Swap system, a new answer to a room that stopped you last time. If you bounced off the base campaign after one clear, fresh heroes plus a reshuffled castle is a more honest reason to return than a new difficulty tier would have been.
Platforms, Price and the Small Print
The practical details, without decoration. The Siege of Castle Doom launches November 10, 2026 on Steam, PlayStation 4, PlayStation 5, Nintendo Switch, Nintendo Switch 2 and Xbox Series X|S; GamesPress’ release also lists Xbox One, so Xbox owners on the older hardware should check their store rather than take either list as gospel. This is DLC, not a standalone release and not a free update: you need the base Marvel Cosmic Invasion installed, full stop.
On price, precision matters more than speed: the only figure on record at the time of writing is $7.99, seen on the US Nintendo Switch 2 listing on November 1. That is a single-platform, single-region listing. It is not a confirmed cross-platform price, and we are not going to round it into one. Check your own storefront tomorrow before you budget the siege; if the other platforms land somewhere else, that is their listing, not a discrepancy.
So, launch eve, honestly assessed: the base game is a good brawler with a great roster and a linear campaign. The Siege of Castle Doom is an attempt to give that roster a structure with a longer memory — routes, perks, a clock, and a host who is also on the character select screen. Nothing about it requires your faith tonight. It requires your $8-ish, your installed base game and one evening tomorrow, and it will either earn the second evening or it will not. Doors open November 10. Pick a hard one first. You know you want to.