itch.io

Stripping back the unnecessary and focusing on the essential. Minimalist games often rely on simple graphics, basic colors, and straightforward mechanics to convey their core gameplay experience. They often prioritize gameplay and user interaction over complex narratives or detailed graphics, providing a refined and uncluttered experience. They may feature limited interfaces, reduced controls, or a focus on a single mechanic or concept.

Science-fiction. Commonly including things like aliens, advanced technology, and settings of outer space or distant planets. 

Unity is a game engine for 2D, 3D, AR and more

Unreal Engine is a 3D game creation tool