Guns of Mercy - Shoot' Em Up is a free Android game developed by Storybird. The game is set in a post-apocalyptic world where Earth's surface has been rendered uninhabitable due to a great war against an alien invasion. Humans are forced to live underground, but the enemy is getting closer. In this game, you play as a Ranger who embarks on a mission to exterminate the alien vermin once and for all.

The game offers retro-style levels with simple and precise controls. You can choose from a range of weapons, characters, and tunes to unlock. There are tons of missions to complete, and you can earn Golds and Gems to upgrade your capacities. With around a hundred levels, the game promises to keep you engaged for hours. The game has received positive reviews from Canard PC, Snapzzila, and Pocket Gamer.

Join the Rangers, blow up aliens, and become a hero in this addictive pixel art arcade game.