Survival
From Undead Assault II Guide
Survival Mode
Quick 1000 exp in 20 mins- 1hr every time.
Pick your MOS. The best MOS's to use in this mode are ones with great mobile firepower. A good example is the Ghost, having Energy Orb and Plasma 'nades give great area damage, crit for burst damage, and Syringe for mobile heal/ailment removal. Most important of all is the Ghost skill pack, containing field cam, flare, light filter (not that there are any krill in survival (at least I haven't seen any yet)) and Ion Cannon for massive area damage. Ion Cannon should only be used when there are either multiple boss/class A/special zombies or a mass of tougher zombies surrounded by hordes of weaker zombies since the cooldown for this skill is ~7 mins. Make sure any squad members have time to get clear before you use it though or you may end up inflicting more damage on your squad than on the zombies.
Note: Navy Corpsmen are just as important in this gamemode as they are in others; if noone else picks an NC, make it your business to pick one.
After picking your MOS, search the abandoned houses for ammo and equipment for ~3 mins. Do not linger too long or you may find yourself surrounded by zombies and get mauled. Note: If you find any EC's, save them for placing at the entrance to your campsite/town. If you don't find any ammo or have too much ammo and no ammo case then just keep searching the ruins. There's usually ammo cases either the right or left of your spawn point.
Sprint to an outpost with some police officers to help defend you. If you find ground flares or can use field cameras, set them up around your camp spot. When you get the extraction mission, bring the marines to the extraction point but do not send them into the copter, instead, camp around the Stryker until you get overrun (in which case evac the 'rines and sprint/flare/smoke/jump to get away) or run out of ammo (in this case you can either evac them and search with some buddies or take the marines with you. Each marine evacuated gives 7xp and a bonus 7xp for extracting most of them (4xp each in outbreak +4xp bonus) You can also have the marines follow you to your camp spot to provide fire support but then miss out on the xp for completing the mission.
In the time between missions, you have a choice: bunker down and camp somewhere or patrol the roads with ~4 others and search for ammo and equipment. If your squad can use some basic tactics such as leap-frogging, your chances at survial increase exponentially, especially with good communication skills.
