The best classes and builds

Here are the classes I recommend, as well as the associated build. It will be worth having it in mastery 5 (so 5 x max level) in order to benefit from all the bonuses.

Medic

Probably the best class in the game, totally essential. Take these liabilities:

• 3: gives a temporary boost of life during the medkit
• 6: gives a health boost when you resurrect an ally
• 8: increases the power of the stim
• 13: starts with an SMG TMP5
• 15: heals you when you use a care kit (no need to use it on you anymore!)
• 18: pickpocket, allows to gain stim charge
• 22 or 23:23 if you are on your allies, otherwise 22 (boost damage after a stim)
• 24: the stims heal, no need to buy healing kits (only take the ones that drop)
• 28: recharge your SMG faster

Support agent

The second best class in the game, you will absolutely need it! It allows you to no longer buy a box of ammunition.

• 1: allows you to recharge
• 6: not very useful, but you need the muni, so neither 4 nor 5
• 7: allows to have a load from the start (see the strat part)
• 11: increase the capa
• 14: double ammo pack
• 17: self-reload (leave the ammunition to your mates)
• 21: faster recharge for automatic
•  24: more balls in the packs
• 28: buff all your defenses

3rd and 4th class

For these other classes, the choices are more free. I advise you all the same at least the exterminator and the infantryman.

The build for the exterminator:

• 3: gives a little survival (we will therefore play mine neither 1 nor 2)
• 6: a little survival too
• 8 or 9: a heavy weapon at your convenience
• 13: your weapon to hold in the beginning
• 15: explosive mine, good control of crossing points
• 18: temporary shield almost permanently
• 23: allows instant recharging when you do a series of dies, brings a lot of clean
• 25: recharge your mines
• 27: increase the max frag by your mines

Before each start, place your mines in the crossing areas, always keep one just in case. You can use it offensively, for example put a mine next to a dead ally (you will take very little damage by its explosion and will be able to save your ally without suffering from zombies).

To begin

Here is the list of things to do for the first waves.

• Use one person's money to buy electric fences, and place it at the top of the ramp to the left of the first area.
• Start searching and use the explosive charge, keep the money on 2 players
• Unlock level 3 weapons + a level 3 weapon pack in the second wave
• Use your heavy weapons as needed to hold wave 1
• Save on one player to continue buying level 3 weapons for everyone

The right things to do

Here's everything you need to do to win easily

• Between each wave, search the map, separate the areas between your mates so as not to search in the same place
• The lurkers and item spawn area are always the same, learn them to search effectively and avoid dying on a lurker
• Do not buy ammunition crates nor first aid kit, nor mortar / machine gun, at least until wave 20 (the stim heal + the provided with the support agent)
• Buy first electric grids, then barbed wire, an auto turret on the first area and auto turrets ready for the military
• Once you have enough fencing, start putting some in the military zone (put full fencing + auto turret + barbed wire)
• Remember to have your weapons to the max!
• If you don't have enough xp, do this technique in normal mode, you will have to take 15 levels at once
• Always keep an electric fence on you