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First-Person Shooter refers to a genre where the camera is at the same place as your eyes: you see (on screen) the scenes just like you'd experience it.

Projects made with the all-in-one cross-platform 2D game development engine

Godot Engine - The free and open source 2D and 3D game engine

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