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Games in which the player shoots things to progress, usually with a variety of guns, and other times with bows and arrows.

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

The larger universe outside of Earth's atmosphere. Sometimes really, really far outside of it.

A perspective where the camera is placed directly above the player. Common in 2D games, but can also be used in 3D games.