Dead Island

This one can be challenging as you have to survive 30 straight waves with another player (so both of you cannot die). Make sure you have a lot of strong weapons and a lot of health kits to repair your health when it gets low. Save your grenades, deo-bombs, molotovs and most importantly use your fury to get through those large crowds or when you get in trouble. You may want to stock up on a lot of grenades, deo-bombs(2x deodorant, duct tape), meat bait(3x meat, bleach), pistol ammo(2x metal scrap, bleach) and large & medium medkits to give you a better chance at survival. You have to be careful when a suicider appears because they can kill if you are too close. To take them out throw a weapon or use a firearm to take them out. Bring a lot of money as well so that you can repair your weapons/upgrade your weapon if they are damaged. This may be easier to do with 4 players, if you are having trouble, look here for help.