Godot Engine
Drop-in replacementFreeThe same engine, from the same download page. Extract it and run it.
Your files: Project folders open with no conversion. Take the .NET build if your game uses C#.
Does Godot run on Linux?
Verdict: Yes
Yes. Godot publish Linux builds on their own download page in the same versions as the Windows ones, and the editor needs no installing at all.
The download page lists Linux builds for four kinds of processor, each in a standard version and a .NET version for C# projects. It is the same release as the Windows one, not a side project.
There is nothing to install. The editor is self-contained, so you download the file, extract it and run it. If you would rather use the Linux app store, there is a Flathub listing, but it is put together by volunteers rather than by the Godot team.
Your projects open unchanged. A Godot project is a folder of files, and it moves between Windows and Linux without any conversion step.
One thing to check. If your game uses C#, take the .NET build from godotengine.org. The copies sold through Steam, itch.io and the Epic Games Store leave C# support out, and Godot say so on the download page.
Godot on Linux, and alternatives
Blender
Different way of workingFreeFor making the 3D models and animations that go into a Godot game, not for the game itself.
Your files: Exports to the formats Godot imports, and Godot reads .blend files directly.
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