Recently, I have found myself fairly disappointed with a lot of the most recent films and games from the Marvel universe. Yet, despite my frustrations with its output as of late, I really enjoyed the release of its 2025 beat-em-up, Marvel Cosmic Invasion. The fun gameplay had me consistently engaged, and the unique cast of characters were a great fit for the space-based narrative. While the game was a bit short and limited replayability were a bit frustrating, I still enjoyed my time with it. So, when Dotemu announced that it would be added a new mode and characters via DLC, I was immediately interested.
While Marvel Cosmic Invasion did add a few other characters post-launch, The Siege of Castle Doom marks the game’s biggest update to date. It adds in two beloved characters, the Invisible Woman and Doctor Doom, as well as the titular mode dedicated to the latter. The Siege of Castle Doom mode combines the beat-em-up combat of the base game with a roguelike style, alongside a mini-narrative focused on Doctor Doom’s activities during the main story. The DLC is a great addition to the Cosmic Invasion formula, even if it sometimes suffers from the same length and replayability problems as the base game.
The first thing you will notice about the new DLC are the new characters. They are unlocked from the very beginning of the game, regardless of your progress in the campaign. Both characters are extremely powerful in very different ways. Invisible Woman can fire a constant stream of projectiles that do quick damage at both short and long ranges. Her projectile allows her to trap enemies in a little bubble, while her special ability unleashes a devastating attack at close range. The attack also instantly turns her invisible, a mechanic that can also be triggered by dashing and allows her to be completely invulnerable for a short time.
As for Doom, he has all the power you would expect from one of Marvel’s most iconic antagonists. He utilizes a mix of hand-to-hand combat and magical abilities to destroy his enemies. His projectiles do damage over time to opponents, while his ultimate can clear out an entire room with a brutal electrical attack. Both characters are fantastic additions to the roster of Cosmic Invasion, and fit right in. Plus, while they do not have any new cutscenes in the main story, they do have unique dialogue for each of its levels. Even if their role in the base game is fairly minimal, the two truly come into their own with The Siege of Castle Doom.
The Siege of Castle Doom is a very unconventional roguelike mode. It focuses on Doctor Doom, attempting to gather power that would allow him to combat the base game’s main villain, Annihilus. In doing so, he threatens reality itself, so it is up to you to stop him. Similarly to the main game, you pick two characters that you can switch back and forth between, and use to summon assists. Unlike the main game, though, the way in which you progress through Castle Doomstadt is drastically different.
Essentially, you must clear out rooms throughout the castle in order to collect batteries from enemies. Each battery fills up one of three charges on a Stabilizer, with each filled charge giving you access to a new stat upgrade. Those upgrades allow you to customize your Technical prowess, as well as your Offense and Defense. Some allow you to adjust the amount of healing you can collect, your melee damage, and your defense against projectiles, among others. Once you collect three charges of the generator, you advance to the next floor and get one step closer to a final battle against Doctor Doom itself.
As you progress further, Doom is getting closer to realizing his plans. The more damage you take and the longer it takes for you to progress through Castle Doomstadt, a meter known as the Siege Gauge will charge over time. With each stage of the Siege Gauge, enemies become stronger and more capable of defeating you in seconds. If the Siege Gauge is completely filled, you lose, and your run comes to an end. However, collecting batteries can decrease the Siege Gauge. When you fill up all three stages of the Stabilizer, you come face to face with Doom for a thrilling final battle that puts all your skills to the test.
The Siege of Castle Doom mode is extremely fun. It offers a challenge that strikes the right balance between being brutal yet fair, thanks to the upgrades you can collect. In addition, the rooms you advance through offer even more perks that will be instrumental in your journey. For example, some may offer you health or abilities that you can use in combat, while others may give you infinite resources for a limited-time. It is up to you to use your understanding of the game’s characters and mechanics to advance through Castle Doomstadt. It is a gameplay loop that is consistently thrilling, and honestly had me far more engaged than I was with the base game.
That said, the sense of progression after each run is fairly negligible. Rather than getting access to permanent upgrades that give you a sense of accomplishment when you finish a run, regardless of whether it ends in failure in success, a majority of the upgrades you get are used to add further difficulty and modifiers to your experience. While it is a cool unlock in theory, its one that does not really feel rewarding. Even the new equipment that you can unlock is a minor upgrade, as the equipment that you get access to throughout a run is completely randomized.
Furthermore, there is not much replayability when you beat a run for the first time. The ending of each run is exactly the same, and is unchanged regardless of which character you pick. Plus, there are not really any new unlocks aside from new color schemes for the characters you beat The Siege of Castle Doom with. Since the runs are fairly short and do not really offer many rewards or changes after once completed, I never really had a reason to play more runs. The abundance of bugs where the game would just freeze, or my run would be ruined by an enemy that was completely inaccessible, certainly did not help matters.
These frustrating oversights are truly unfortunate, considering just how much fun The Siege of Castle Doom mode is. Still, the DLC as a whole is a fantastic addition to Marvel Cosmic Invasion. Despite its oversights, the fun new characters and exciting gameplay of the new mode genuinely improves the base game in a way that I did not think was possible. Whether you already own the base game or have been waiting for an excuse to jump in, The Siege of Castle Doom is an absolute must-play.
Disclaimer: Dotemu provided a PC (Steam) copy of Marvel Cosmic Invasion – The Siege of Castle Doom for review purposes.
