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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.

Sprites are generally 2D images used in games to represent objects. They can be animated or static, and come in different styles like isometric or top-down.

Shooter games with a top down, birds eye view of the characters surroundings.