Reference Library
Skyler's collection of open-source games and assets to study or build on. Last updated 2026-10-09 (Pass 1 research).
Goal and how references are used
The aim is to make original games in Unreal Engine 5 and Construct 3 without starting from zero. This is not about re-releasing freeware as-is.
- Study: read targeted parts of a game's code (combat, weapons, enemies, level and content systems) to pull out specs, structure and tuning values. Most useful for niche or loosely defined genres, such as a Madness-style action game, where there's no written spec.
- Foundation: permissively licensed code or assets used as a starting point, then reshaped into something new.
- Testing: Claude can check that a build boots, renders, takes input and holds a frame rate in a headless browser. Game feel and networked play still need a human.
What's in the library so far
Nothing is cloned or downloaded. The candidate list is Pass 1: a wide, shallow sweep from curated lists, GitLab and npm metadata, plus a hand-picked set of well-known games and starter kits. Licenses are only what each source lists. Pass 2 will read the raw license text.
How Pass 1 filtered
- Auto-rejected: non-commercial or no-derivatives or proprietary licenses, GitLab repos with no license detected, dead repos (no activity since 2020 and almost no stars), and npm packages that were junk, had no repo link or had no usable license field.
- Kept and flagged: everything else. Flags: code license unclear, assets unclear / mixed / proprietary, activity unknown, inactive 2y+. Buildability is unknown for all.
- Sorted by fewest flags. The code-only reference tier holds good code whose original game data is proprietary (Doom, Quake, Morrowind and similar).
- Not covered: Codeberg, SourceHut, SourceForge, itch.io, js13kGames and LibreGameWiki could not be reached, and PyPI has no search. GitHub entries come from a separate GitHub search pass and the curated lists; licenses there are as GitHub detected them.
Candidate table
Entries tagged verified or problem were checked against the repo's LICENSE and README in Pass 2 (135 shortlist entries; asset provenance is only as good as what the repo states). Every other license here is unverified: it is what a source listed, or from memory for the hand-picked entries. Check the repo's LICENSE file and asset credits before relying on any of it.
Port confidence is a rough 1 to 5 guess at how easily it could be built and run in a browser for testing (5 = easy). Use: study = read only, foundation = may be built on if the license holds up.
| Game | Genre | Engine / build | Code license | Asset license | Port | Use | Flags |
|---|
Gallery
Drop a screenshot into the images folder using the file name shown on the placeholder. Featured entries show first; the rest are behind the button.
Licensing rules of thumb
- Code and assets are licensed separately. A game can have MIT code and non-commercial or all-rights-reserved art. Check both.
- Permissive (MIT, zlib, BSD, CC0): the commercial lane. Usable in a closed-source paid game with attribution as required.
- GPL: fine to study and to learn tuning values or structure from. Shipping GPL code means releasing your game's source under GPL, so treat it as study-only or free-release.
- CC-BY / CC-BY-SA assets: credit required; SA means derivatives must use the same license.
- CC-NC (non-commercial): study only for a paid game.
- Never ship original Doom or Quake assets. The engines are GPL, but the original game data is still commercial. Freedoom and similar replacements exist for a reason.
- Ideas, mechanics and tuning numbers learned from reading code aren't copyrightable, but copied code and art are.
Where to look for more
- GitHub: topic tags like game, godot-game, open-source-game
- GitLab
- Codeberg
- SourceHut
- SourceForge: older but deep catalog
- js13kGames: tiny, readable browser games
- Game jams: Ludum Dare, GMTK, Godot Wild Jam entries with source
- itch.io: the open-source tag
- npm / PyPI: small games and game libraries
- Engine galleries: Godot showcase and demos, Phaser examples, Three.js examples
- Linux repos: Debian games team, Flathub
- LibreGameWiki: curated list of free games
- OpenGameArt: mixed licenses, check each asset
- Kenney: CC0 asset packs
Cloning from hosts other than GitHub may be blocked from Claude's sandbox, so those may need a manual download.
Open questions for Skyler
- Which genre should the first original game be? That decides which references matter most.
- UE5 or Construct 3 for the first project? It changes whether 3D shooters or 2D references come first.
- Is the first game meant to be sold? If yes, only permissive code and CC0/CC-BY assets can go in it.
- Pass 2: which entries should get a raw license check and screenshot first? Suggestion: the permissive, no-flag ones in your favorite genres.
- Do you have a specific Madness-style game in mind for the .NET 9 study target?
- Should this page stay a single file, or grow into a page per game with notes?