itch.io

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. 

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.

Games that can be played alone