CthulhuJam 2025

About

Welcome to CthulhuJam 2025, brought to you by Cthulhian Coding Corner. This is our first game jam, and hopefully not our last. This is a game jam where we make games inspired by cosmic horror, ancient entities, and general weirdness. Whether you're building a text adventure, a platformer, a puzzle game, or something that defies categorisation entirely, we'd love to see what you create.

The theme will be up for vote very soon, so keep an eye on the server for that. The main goal here is to have fun and make something cool together. No sanity checks required (though they might be recommended).

Rules

• Build your game during the jam period
• There's no limit on team size, but we recommend teams of 3–4 people. Solo is totally fine too if that's more your style.
• Any genre works. Seriously, any genre.
• Your game must run on Itch.io using a web export (HTML5/WebGL/etc.). If it doesn't run in a browser, it doesn't count.
• You can use existing assets, but making your own stuff is always more fun. Plus you get bragging rights.
• Your game needs to actually run and be playable. No "it works on my machine" shenanigans here.
• Write a quick description of what you made. We'd love to understand your beautiful creation.

That's it. We're keeping this simple. No ancient rituals required (unless that's your game's theme).

Submission

Upload your game to Itch.io and submit it to this jam page before the deadline. Make sure your game runs directly in the browser using a web export. Your game page should have:

• A playable web build that runs on Itch (this is important, we can't stress this enough)
• Some screenshots or a trailer so people know what they're getting into
• A description of your game (we'd love to hear your story)
• Credits for any assets you didn't create yourself (be nice to the creators)

Even if your game isn't complete, please share it anyway. An MVP is a great way to gauge a game, and we'd much rather see what you've got than nothing at all. Imperfect games are still games, and sometimes the jankiest ones are the most fun.

Timeline

You've got the first two weeks of December 2025 to build your game. Submissions close at the end of week two (no extensions, sorry – the cosmic entities are strict about deadlines). Week three is when everyone gets to play the games and vote. We'll announce the results on Christmas Day, because what better gift than finding out how your game did?

Judging Criteria

Once submissions close, all games will be ranked according to the following categories. Each category matters, so aim for a well-rounded entry:

• Gameplay – How engaging, clear, and enjoyable the game is to play.
• Quality – Technical stability, polish, usability, and overall execution.
• Cohesiveness – How well the art, sound, mechanics, and theme blend into a unified experience.
• Originality – Creativity in design, mechanics, ideas, or presentation.
• Theme Adherence – How effectively the game captures and expresses the jam’s chosen theme.

Community voting will use these criteria during week three of the jam.

Questions?

Got questions? Drop a comment on this page or hop into the Cthulhian Coding Corner server. We're here to help, and we promise we won't judge your questions (probably).

Have fun, and try not to lose your mind in the process. If you do lose it, at least you'll have a game to show for it.