Hunt the forest for all sorts of animals. There are secret objects what will get you bonus points as well as you can lose points by shooting the wrong things. Try to unlock different skin types by completing each levels.
All your team members are dead and you're the only one survived. Just stay alive as long as you can and don't forget you are low on ammo, use 'em wisely.
Defend the hill against all mindless zombies that assumed it to be their home. Use 19 powerful weapons including the hand cannon, hunter pistol and the jackhammer to destroy them.