When I reviewed Marvel Cosmic Invasion at launch last December, I enjoyed the game quite a bit as an old-school beat ’em up, but lamented its lack of replay value.
About 11 months later, that replay value has arrived in its new DLC, The Siege of Castle Doom. The expansion adds both Doctor Doom and Invisible Woman as playable characters, but also a whole new game mode for players to group up and have fun with. And it’s carried by the industry’s favorite new old reliable, roguelite mechanics.

The Siege of Castle Doom tasks players with mowing down waves of foes, including new Doombot enemies, and moving from room to room by choosing where to go next, similar to classics in the genre like Hades. Doors within Castle Doom have different icons on them, and they offer different rewards, but in the end it’s all about slaying enemies as quickly as posible.
But there’s also a Siege Counter on the bottom right of the screen that fills up as you play, making enemies stronger and quicker. Once that gauge fills, the run is over, and you have to start from scratch once again. This puts a lot of urgency on killing enemies as fast as possible to gain batteries to charge up your upgrades, fighting bosses from the base game to lower the doom gauge and keep yourself alive long enough to face the final boss, Victor Von Doom himself.
But there’s also a sense of progression in the mode in that you use charges gain to unlock permanent stat upgrades and very special unlocks. These include powerful, game-changing modifiers like gaining an extra life instead of a second hero, or equipment like Vibranium (25 bonus HP for 10 seconds) or SHIELD Turret (summon a HeliCarrier turret for 7 seconds).
The DLC mode differs from the base game in that enemies drop batteries that you use to charge up an item on the bottom left of the screen. Filling up that gauge rewards you with a choice of a buff (Offensive, Defensive, or Tactical), as shown in the screenshot above, making each run feel unique, and this is the main mechanic behind clearing the mode. Kill enemies, grab batteries, charge up abilities, and make it to the final boss fight.

The randomness of a run of Siege makes it fun, like any roguelite before it, but the gameplay does not reinvent the wheel by any means. This is the same fun Marvel Cosmic Invasion combat, now more replayable and with two more playable heroes (which is exactly what I wished for at launch), and both are quite powerful.
Doom is a tankier, slower playable, using melee attacks combined with magic green lightning to clear the screen, including a projectile that debuffs enemies. Invisible Woman, meanwhile, moves a bit quicker, has a ranged attack that can freeze enemies in place, and can fly, making her my favorite of the two new heroes. She can also go invisible, of course, giving her a few seconds of safety from enemy attacks. But make no mistake, Doom hits hard, so he’s worth trying out as well.

This DLC is genuinely a good time that adds on to an already-fun game, and for $7.99, worth the price of admission, because it’s easily replayable and enjoyable especially when you bring a Marvel fan friend along for the ride.