Survive the night fighting off zombies from your barricade. Survive longer than a day by making use of the daylight hours effectively by repairing your barricade, searching for weapons and looking for other survivors to help repair and defend.
You are sent out into the desert on a diversion mission. You must survive enemy attack for six days until main forces will take over. Defend your desert position for six long days.
It's a nightmare. You are trapped in an abandoned mine with an injured comrade at your side against God-knows-what. Make your stand, get out alive. Three words of advice: shoot to kill. These things are not human, they are monsters..
Another Doom style game called "Flatten Horizon" with top view game play. Plenty of monsters, weapons, blood and doom like action in different perspective.
You and a handful of others form the Last Line of Defense, pooling your remaining stockpile of weapons, special ammo, bunker defenses, and super-weapons to fend off the onslaught by virus infected, bloodthirsty Ravagers.