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Featuring extraterrestrial beings, these games often explore themes of space travel, alien invasions, or interstellar diplomacy. Encounter mysterious life forms, defend against alien threats, or uncover the secrets of the cosmos in these otherworldly adventures.

Shoot 'Em Up or shmup games are a subset of shooter games where the player continually moves forward while waves of enemies enter the screen. Both shooting and dodging are critical to advancing. See also Bullet Hell.