Caliber is a game that is based on the happenings of a Zombie Apocalypse. Use the training tutorial if you think you'll have trouble catching on. It's a fairly simple bird's eye view game where you control yourself with the W,A,S and D keys and shoot with the mouse. Use the R button to reload. Try to reload often so you're not caught reloading with a zombie breathing down your neck. Use Survival Mode or Free Range Mode to play. Collect weapon upgrades and toggle through them with the Q or E buttons. See if you have what it takes to survive wave after wave of flesh eating undead in Caliber.