unity3d.com/
Unity is a game engine for 2D, 3D, AR and more
Pretty sure everything is indie on itch.io but just in case you want something extra indie.
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The larger universe outside of Earth's atmosphere. Sometimes really, really far outside of it.
Explore games made with Unity tagged Indie and Space on itch.io · Upload your games made with Unity to itch.io to have them show up here.
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