nunuStudio
Web powered cross-platform 3D, WebXR game engine
...As an accessible entrypoint to game or interactive content creation, nunuStudio is well-suited for artists, designers, or developers who prefer a WYSIWYG (what you see is what you get) workflow instead of fully coding everything. Because it is open source, users can inspect, modify, or extend the system as needed — adding custom behaviors, plugins, or export options.