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Simple, fast-paced games with colorful graphics and catchy audio, that require few or no explanations, can be played in short bursts, and usually require a lot of skill. Similar in style and spirit with the arcade game cabinets of the 80s and 90s.

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

Games where the primary goal is keeping the player character alive under harsh circumstances such as dwindling resources or a hostile environment.