Cosmos Fighter is a pixel-art game; a mix of two genres, tower-defence and roguelike. You have to protect your space-ship, build and upgrade the defence (along with weapons), and fight with bosses.  The game is mostly single player, but you can play with your friends in cooperative mode. 

Story

You and your friend, mechanic, crashed the space ship into the Moon, because of a problem with the engine. Unfortunately, you landed on the territory of the enemy superpower. The military thinks that our heroes are enemies, so they attack. While the mechanic is trying to fix the ship, you are defending it and trying not to die. 

Features:

• 10 levels
• About 1 hour of gameplay
• Cooperative mode 
• Boss fights