This guide contains information you need to know about leveling up, the progressive skill tree builds and the level 500 builds.

Below are the suggested xp farm methods.

In general,
For lower levels, kills worth more xp.
For higher levels, objectives worth more xp.

If you are solo, you are good to go, if not, change server.

Grab ak -> finish the first objective -> vote compound to restart game

The objective xp is nearly negligible at low level, you may not need to restart if this is the case.

If you are solo, you are good to go, if not, change server.

Enter game -> check if objective is kill X zombies
If not -> restart game
If yes -> grab revolver -> kill zombies until briefcase mission (you should secure library as well if you can) -> try to complete kill 75 walkers in the side quest -> restart game

Restart game = leaving and joining / vote termoil to restart if cooldown is done

The objective xp is nearly negligible at low level, you may not need to restart if this is the case.
Also you maybe very unlucky at getting kill X zombies objectives. If you are unlucky, consider other methods.
There is no easy-to-grab ak. You can get famas, but it is inferior. Consider other methods if you want ak.

You can also consider finishing the whole map. I tested in local game, I could finish termoil starting with level 16 and finishing at level 21. The build used were the suggested build discussed in latter part.

Grab ak -> grab grenades -> use 3 grenades to kill 20+ zombies -> kill some more zombies -> gunslinger should be ready -> clear the remaining zombies with gunslinger -> vote ambit to restart

Several options below:

Recommended:
Get deagle in front of the project zero door -> kill zombies

Hit some bandits in the sewer to get ak / ask for an ak -> kill zombies

Less recommended:
Go to the ventilation shortcut on the right hand side after going out from base -> go through the ventilation to the train station -> grab minigun -> go back to base -> kill zombies

Go to library and get famas -> kill zombies

Note that this assumes that you use the recommended build discussed below, and assumes that you have chosen lifesteal first. If not, you should attempt this only when you have good enough dps and lifesteal.

This method requires good skills because the bandits wave is quite difficult to solo. You can fall back to wave 1 farm if you have difficulties to complete the map.

Wave 1: Walkers
@Ambit wave 1 solo farm
Grab ak -> grab grenades -> use 3 grenades to kill 20+ zombies -> kill some more zombies -> gunslinger should be ready -> clear the remaining zombies with gunslinger

Wave 2: Bandits
Grab ak -> grab grenades -> stay near center and wait for bandits spawn -> when bandits spawn, go towards ak so the bandits will not shoot you immediately -> throw grenades to kill bandit groups -> obtain minigun -> use minigun to clear the wave

Wave 3: Runners
Too ez to discuss...

Wave 4: Chaos
The real juice is here.

Grab smg -> grab grenades -> use the 3 grenades -> find the minigun (look for a fire extinguisher container floating in the air) -> clear enemies with bandits as prioritized target -> always swap minigun with the minigun drop to refill ammo

Wave 5: Turtles
Hug them for good dreams. I mean kill them for xp.

Player A (less experienced player) rushes objectives.
Player B (more experienced player) rushes side quest.

A:
Kill zombies / get briefcase / secure library -> get bandit item -> melt fred -> get bandit item -> get radio and wire -> sleep at sniper room in the base -> escape

B:
Break a hole on the project zero door when heading to the train station -> farm runners at the train station -> kill bandits -> (may need to melt fred in the middle) -> help with objectives (should be at radio and wire now if things are going smooth) -> sleep at sniper room in the base
-> escape

You should have gunslinger ready to melt fred quickly.
After pouring bullets on fred's head with gunslinger, if fred is not dead, go to base and chop fred. Fred will get stuck at the entrance of the base.

Grab ak -> do objectives until finishing securing the church -> vote coltec to restart game

Bandits wave:
Stand on the staircase to prevent zombie spawns, as shown in the pictures.

Fred:
Stand on the spiral staircase, fred cannot enter.

Kill zombies -> pick up data module -> turn on generator + turn in data module -> pick up minigun -> melt fred -> collect fuels -> faster player waits for briefcase at burning helicopter -> collect briefcase -> kill zombies -> escape

At the time I write this guide, there is a bug that if you turn on generator too quickly at the beginning (before light going off), the generator will go down and you cannot immediately turn on generator again. So don't turn on generator until data module.

This is the method I used.

Note that the zombies spawn wave by wave.

Kill one wave of zombies -> trigger nuke -> kill another wave of zombies -> should have gunslingers ready -> melt fred -> when fred is low hp, one player goes to basement and waits for briefcase -> collect briefcase -> escape

Your enemies are military. As long as they can't steal your kills, you should complete the first objective within 2 waves. If you cannot complete the first objective within 2 waves of zombies, it indicates that your dps is problematic. You need to work on your speed and study the behavior of the zombies.
Note that It is about how many kills stolen by military, not about how fast you kill some zombies.

Note that if you solo, you definitely cannot complete the first objective within 2 waves because your kill speed is too slow. If there are more than 2 players, the kills required will exceed the number of zombies in 2 waves. Hence, exactly 2 players only.

This is the method my friend used.

For zombies wave:
Kill all

For bandits wave:
Kill bandit leader and grab minigun -> kill all

Please use the suggested build (discussed in latter part) for this.

This is newly added when I am already level 500. I cannot test how fast this is, but it should be fast...

If you burn out from farming, you will end up slower. Just play the game.

Below consists of builds you should use while leveling up.
You can remove skill points by right-click.

Most important thing. This skill will heal you as well. The skill is recharged by killing a certain amount of enemies (maybe 40? not sure).

Out run the runners is important.

Now you can shed zombies easily. You can start doing different maps with this.
Note that you are still weak because you don't have heal.

For flaming bullets, lighting up a zombie = kill. To preserve ammo, shoot the zombies that are not lit yet.

Now you don't have to rely on medkits and ultimate skill to heal.
I suggest getting lifesteal first, but it is up to you to decide.

Can't die easily now.

Now you should be at level 110-ish or something (I don't remember). This is fairly easy to get. The grind just started. I allocate skill points such that you can enjoy high dps.

Kicking at the head does 128 damage.

Fire rate for killing bandits.

Now you can use deagle. At the time I write this guide, it does 217 headshot damage.
When using deagle, use one handed mode.

Switch back to melee now because you can fully upgrade melee.

I have tested and will keep testing the builds to make sure the builds are meta. These builds take all of the most important skills to greatly boost dps and handle all kinds of situations. The following are two skeletal builds. You can customize the builds according to the guidance provided.

One gun of your choice + machete/fireaxe

Troll Tolerant
Imagine you are securing a room, while 5 player zombies are chasing you because they don't want the completion achievements so badly. You can stand forever in the room swinging your blade.

Extreme dps
Machete bleed damage is 106 damage per tick on fred.
Fireaxe bleed damage is 81 damage per tick on fred.
If you heavy blow + kick at the head, and proc the bleed, you do over 1000 damage for just one attack.
Rifles with all skills except only level 9 fire rate, but doesn't matter, it just pierce everything.

Fast Objective Speed
You don't need ammo. You just keep moving and vaporizing anything on your path.

Against zombies
For guns, you know the drill.
For melee, light attack + kick at the head will always one hit in normal server (236 damage for one blow).

Against bandits
If you are at the corner, spam melee swings so they get grind when they go through the corner.
If you are at a range, use rifles to shed.
If you are at close range but not close enough to melee hits, you slide and chop.

Against fred
Note that fred will trigger if it takes a heavy hit. Therefore, there are two options.
Option 1
If the fred can be stuck at a door or something (like in termoil), use melee as primary weapon.
As mentioned before, one heavy blow + kick + bleed > 1000 damage, only heavy blow on fred's head when fred is not bleeding. When fred is bleeding, use light attack or use rifle to light it up.
Option 2
If the fred cannot be stuck at a door, do not use melee.
Use rifles to grind it to its death.

Against player zombies
Melee heavy blow + kick usually one hit them. If you miss, switch to rifle and vaporize them.

Change rifle skill to other weapon skills to use other types of guns.

All guns

Guns Compatibility
You can pick up whatever guns you see and kill everything.
"I don't know, I just picked up a pistol then I couldn't find any zombies anymore."

Extreme Burst dps
You can clear a group of zombies with one clip easily.

Just shoot everything on sight.

You can remove weapon skills for other skills. One recommendation is replacing sniper skill with freezing bullets.

Read this if you are interested in details. You can ignore this part as I intend to hide details to bug you less in the guide.

First of all, for the max efficiency, you should only allocate one point for ultimate skill.
Becoming a ghost and going through zombies is inferior to shooting a path out by your gunslinger.
Increased melee attack speed and heal is inferior to infinite ammo. Moreover, the skill already heals you to full hp, so the advantage of the heal is questionable.

Speed is the most important because you need to out run the runners. However, reduced weight is less important (not used in my builds). I found that the effect is not even noticeable (maybe no effect) when using normal weapons. The only weapons / items that will reduce your speed are the heavy items: sledgehammer, minigun, flamethrower, armor. Just don't use these without reasons then you will be fine.

Melee stun skill proc chance is too low to use...

Utility skills (slide, jump) are conditional, I don't find them useful, given you have to trade some dps for easier movement. Also practicing your crouch jumps will just eliminate the needs of jump skill.

Armor and medkit buff are useless if you don't get hurt / you are healed instantly by lifesteal. Getting max dps and relying on lifesteal is better than lowering dps for some item buffs. Also the items are shared with other players. It will kill you if someone else uses the medkits/armor.

Freezing bullets offer no damage. However, it can stop enraged freds from running. You can consider this as bossing support skill.

Ammo replenish buff is not useful because you always clear the zone before refilling. Marginally useful in mecklenburg arena, but it has minigun now.

Rifle > secondary > shotgun > sniper

The guide offers a tested path for farming. It focuses on max power for builds. After all, builds are personal. You can modify and test for other variations to suit your style.

Thank you for reading this. I hope this helps with your farm.
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