# MARVEL Cosmic Invasion releases Siege of Castle Doom DLC for Linux and Steam Deck

> **Key takeaway:** The new DLC adds a dedicated game mode, two playable heroes, and new mechanics to the MARVEL Cosmic Invasion brawler.

**Published:** 2026-11-12T15:50:04+00:00 
**Source:** Linux Game Consortium 
**Category:** open-gaming 
**Canonical URL:** https://fosswire.org/news/marvel-cosmic-invasion-releases-siege-of-castle-doom-dlc-for.html 

## Summary
Tribute Games Inc. and Dotemu have released 'The Siege of Castle Doom,' a new DLC expansion for the arcade-style brawler MARVEL Cosmic Invasion. The update introduces a new game mode centered around infiltrating Doctor Doom's residence to stop the Cosmic Inductor, featuring roguelike elements such as randomized paths and 12 different perks.

In addition to the new mode, the expansion adds two playable characters: the Invisible Woman and Doctor Doom. The content is available on Steam for Windows, Linux, and Steam Deck, maintaining the game's native support for these platforms.

## New gameplay mechanics and character additions
- **New Playable Heroes:** The expansion introduces Susan Storm (Invisible Woman) with light-bending and force field abilities, and Doctor Doom, featuring high-tech armor and hidden skills.
- **Roguelike Elements:** The Castle Doom mode incorporates procedural elements including new foes, varying paths, a race against time, and 12 distinct perks that modify defense or damage.
- **Progression Systems:** Players can acquire permanent gear through Reed's lab and unlock new color sets by defeating the DLC's primary antagonist.
- **Platform Compatibility:** The DLC is confirmed to support Linux and Steam Deck, ensuring parity with the Windows version of the base game.

## Why it matters
The release reinforces the importance of native Linux and Steam Deck support for arcade-style brawlers. By ensuring the DLC functions seamlessly on handheld Linux devices, developers like Tribute Games continue to expand the library of high-quality, playable titles for the Steam Deck ecosystem.