Play 13 Days in Hell Unblocked - There's nothing worse than a bunch of scary zombies walking the earth. Do a tour of duty in the underworld, and destroy them all. These zombies wont stop coming, don't let them take you under! How to Play: Mouse to aim and fire. Use the red dot to determine the perfect moment to fire. Keys 1 to 5 or the mouse-wheel to select a weapon. Spacebar or R to reload. A high difficulty level earns more points! (and makes the game more challenging and enjoyable) 13 Days in Hell unblocked is Rated T for teens.