Infecteds

 Infected are the main threat for the survivors, the infected's objective is to eliminate all the survivors or beat them in Deathmatch 

Infected Types= These are the zombie types you can play as when you are in the Zombie team. Click the images to go to their own pages!

Summaries
Normal Zombie (Threat level D) - The basic and most common zombie, they're not a huge threat, it has only 125 hp and no abilities making it a weak foe, but they can spawn with the armor that you are currently wearing. You should buy a more dangerous zombie type after you spawn as it.

Crawler (Threat level C) - The cheapest zombie to buy among all zombies. It is a fast zombie that jumps high and runs fast making it harder to hit. However, it can't climb ladders. You should have a good aim to kill this zombie if it's dodging.

Bloater (Threat level C+) - A fat zombie full of toxic puke, he can puke at you to make it harder for you to see, and he explodes on death dealing massive damage to nearby enemies, but his speed is quite sluggish compared to the other zombies. You should kill it at a distance.

Tangler (Threat level B) - A zombie with a huge tongue that tries to capture you with it, if you get captured you will be disarmed and will take damage with time unless someone kills the tangler or if you escape with the Machete. You should kill Tanglers first if you don't have a teammate or a Defender or a Machete.

Hunter (Threat level A) - A slow, crawling zombie that can lunge at high speeds. Attempts to dodge are usually futile, and if you get caught by it, you will be pinned and take damage until you or the hunter dies. It's only way to move is to lunge, which can only be done 4 times before it has to recharge it's stamina bar, but it can easily punish players who wander off from the rest of their group. Although it is not strong, its still one of the most dangerous zombie in the game, probably behind only the Juggernaut. However, it can't climb most ladders. You should always kill it first, especially when you have no teammates and a Defender around to save you. This zombie received alot of hate by many people and want it to be nerfed or even removed, for makes the game unfair for survivor players.

Banshee (Threat level A) - A seemingly harmless zombie that just cries, at least until it takes damage. Then the banshee would be startled and would get invincibility for a few seconds then will attack, running at great speeds, and dealing great damage per hit. However it can't climb some ladders.

Riot (Threat level B) - A zombie that is wearing riot control armor. It attacks using its baton, and can do a shield rush which gives it immunity to all damage until it hits a wall, which often ends with one or more players having their health lowered a lot. It is the only zombie immune to critical hits from headshot, as It's headgear makes it immune to headshots.

Spitter (Threat level C) - This zombie will try to spit what looks like acid at you which can slow and damage you. Can be useful to deal extra damage to survivors that have been pinned down by Tanglers/Hunters to kill them faster.

Francisco (Threat level B) - This zombie has the ability to cloak themselves. When they attack a survivor while being cloaked, they will blind the survivor for a few seconds, allowing other zombies to come and deal damage to the blinded survivor. Very situational, but also very useful. This is useful in Capture Points.

Inferno (Threat level A) - An entity made out of fire which can combust, causing it to explode (hence the name, "Inferno") and deal fire damage to anyone nearby and will heal it, the Inferno is also immune to any fire based attacks like explosions, but its weakness is the Fire Extinguisher, because it deals heavy damage to it. You should kill it as fast as possible.

Chiller (Threat level B+) - An entity made of pure ice. His attacks can slow you down and his "Chilling Breath" ability can freeze you making you disarmed for a good amount of time and stuck in place, totally defenseless. His weakness is the Baseball Bat since it shatters and kills him with one hit. It can be damaged heavily by fires. Although their Chilling Breath attack can be devastating, it can be avoided rather easily if you don't get close to the Chiller, compared to the Hunter which can get to you very quickly. Can be useful for Hunters, Tanglers and Bloaters.

Shaman (Threat level A) - An mystic magician that can heal its zombies. It uses its staff which there are 2 magics: "Heal" and "Curse". Once it use the "Curse" ability, the red particles will appear on a player, this can allow zombies to deal extra damage to a certain player for a few seconds. It has a massive amount of health, which is higher than Banshee. The newest zombie in the game, added in the Infected Update on 5.8.2.

Juggernaut (Threat level S) - A very tough zombie, it can deal tons of damage by hitting you, their rock throwing attack is a massive damage dealing attack, and you should be extra careful. However, it can't climb ladders in most maps. (Your gonna have a hard time killing this if none of your teammates are helping you, as its only weakness is ladders.)

Removed Zombies
Slimer (Threat level D) - While not much known about this zombie, it has 100 health making it a weak foe. It looks like an actual Normal Zombie but an entity made of slime which probably cover your screen green making you harder to see. This was removed in 2018, making it the first infected to be removed from the game.

Charger (Threat level B) - This is the most wanted and requested zombie in the game. It is a zombie that wears a farmer shirt and hat with a huge arm. It acts similar to Riot, being able charge, but it can probably allow it to grab a survivor when charging towards them. This zombie was removed from the game for being too overpowered, making it the second zombie to be removed.

Trivia

 * Slimer was the only infected that got removed.
 * Charger used to be in the game but was removed for being too overpowered.
 * Some of the zombies' name used to be called that is based off any Left 4 Dead infecteds, which was changed due to copyright reasons.
 * Bloater used to be called Boomer.
 * Banshee used to be called Witch.
 * Juggernaut used to be called Tank.
 * Prior to 5.8.7, Normal Zombie, Crawler, Bloater, Tangler, Hunter and Riot were used to use your avatar's face.
 * This was replaced with zombie-like faces after this version, probably due to avatar face makes an Normal Zombie look like a survivor.
 * Shaman is the newest zombie to be added in the game, being added in 5.8.2.