Zombies are ruling the world and the last hope for people is you. Shoot down the incoming enemies and don’t die.
It’s an action game with only one goal – destroy all undead enemies from the first person view. They are coming and you should be ready. Take a weapon and get them. Your fort mustn’t be breached. The money you gain can be invests into buying some special items, or to repair the place, or you can get some nice new weapons.