Let's be honest. Zombie classes are the definition of s-h-i-t.
Well, not bashing SeV or anything, but you could really use some balance and new classes. Maybe a bit of variety too.
Currently, the classes are:

Default Zombie - Standart Infect - 0 XP
Mutated Zombie - Infect with drunk vision (-5HP) - 500 XP
Hunter Zombie - High jump - 3000 XP
Witch Zombie - -45 HP Damage - 10,000 XP
Boomer - Explodes and Infects on death - 25,000 XP
Tank - Throw all around, -5 HP - 35,000 XP
Screamer - Force all around to the ground - Rank 15
Advanced Mutated - Infect all around - 65,000 XP
Heavy Screamer - Throw all around, +5 HP - 80,000 XP
Flesh Eater - Infect (Drunk vision), -10 HP - 100,000 XP
Advanced Screamer - Throw all around, +10 HP and -10 HP to Human - 250,000 XP
Advanced Witch - -69 HP Damage - 400,000 XP
Advanced Tank - Throw all around you, -15 HP - 650,000 XP
Burning Ashes - Throw Molotovs - 850,000 XP
Experienced Tank - Throw all around you, -25 HP - 950,000 XP
Experienced Witch - -89 HP - 1,000,000 XP
__________________________________________________________________________________________________

Not only are they very few, very expensive and pretty useless most of the time, they are also very unbalanced.
First, I'll go ahead and try to balance them for the sake of it.

Default Zombie - Standart Infect (-3HP) - 0 XP
Mutated Zombie - Infect (-5 HP) - 500 XP // Damage increased to 5, Drunk vision added (It doesn't work)
Hunter Zombie - High jump - 3000 XP // Nothing changed, this class is good enough.
Witch Zombie - -50 HP - 5000 XP // It's a pretty shit class for 10,000 XP. Damage increased to 50.
Heavy Zombie - 7500 XP // To fill the gap between 5k and 10k XP. It's just an ordinary zombie, but with a twist.

Heavy Zombie "card"

Skin ID: 182
Skill: Default Infection
Weapon: Fists
Health: 200
Armor: 0

Reaper Zombie - Chainsaw with increased damage, 10,000 XP. // Yep, bring this old class again.

Reaper Zombie "card"

Skin ID: 77
Weapon: Chainsaw
Skill: Increased Damage
Health: 100
Armor: 0

Boomer Zombie - 20,000 XP - Explodes and infects on death - Has 50 HP only // Reduce the XP requirement to 20,000 XP.
Tank Zombie - 27,500 XP - Throw everyone around, -5 HP // Reduce XP requirement to 27,500 XP.
Rogue Zombie - 35,000 XP - Has a human skin and a human color // A pretty stealthy class. :D

Rogue Zombie "card"

Skin ID: 202
Weapon: Fists
Health: 100
Skill: Human color & Human skin
Armor: 0

Knife Zombie - 45,000 XP - Has a knife, heavy damage // Deals heavy damage.

Knife Zombie "card"

Skin ID: 137
Health: 100
Armor: 100
Weapon: Knife
Skill: Knife deals 50 HP damage.

Advanced Mutated - 65,000 XP / Infect all around (-5 HP) // It's good enough.
Heavy Screamer - Throw all around, -5 HP, 75,000 XP // Reduce the XP requirement to 75,000, and change +HP to Zombie to -HP to Humans. 5HP doesn't really help Zombies at all.

Flesh Eater - Infect (Drunk & -10 HP), 100,000 XP // It's good enough, don't change anything.
Burning Zombie - Set those who are around you on fire, 150,000 XP. // I think we had this one before?

Burning Zombie "card"

Skin ID: 136
Health: 100
Armor: 0
Weapon: Fists
Skill: Set all around you on fire

Ghost Zombie - Can "Possess" one human, turning him into a Zombie. Can be used once every 3 minutes // 200,000 XP

Ghost Zombie "card"

Skin ID: 133
Health: 100
Armor: 0
Weapon: Fists
Skill: LALT when you're next to a Human to instantly turn him into a Zombie. Can be used once every 3 minutes (180 Seconds)

Advanced Screamer - Throw all around, +10 HP to Zombie and -15 HP to Human - 250,000 XP // Increase HP damage to -15
Radioactive Zombie - Flesh-melting infection, -20HP per second. // 350,000 XP

Another class to fill the gap between Advanced Screamer and Advanced witch. Pinnacle of infections.
Radioactive Zombie "card"

Skin ID: 159
Health: 100
Weapon: Fists
Armor: 0
Skill: Very deadly infection. -20HP/S

Advanced Witch - -75 HP Damage - 400,000 XP // Increase the damage to 75 HP.
Advanced Tank - Throw all around you, -20 HP. 600,000 XP // Reduce XP to 600,000, increase damage to 20 HP
_________________________________________________________________________________

Burning Ashes
(Custom skin)

We've got Burning Zombie that does nearly the same thing that Burning Ashes does, so let's change this fella's skill.
Burning Ashes - Create an explosion wherever you're looking. Explosion ID 0, 850,000 XP // Just change the "molotov" effect to explosion ID 0, tada!

Experienced Tank

Remove this class, it's really unnecessary and sucks anyway, lol. We're going to replace it with..

Spitter Zombie - Infect all around you, -20 HP/S. 950,000 XP // Yep...
(Custom skin)

Skin ID: 5
Weapon: Fists
Armor: 0
Health: 100
Skill: Infect all around you with very deadly virus. -20 HP/S

And now.. Well.

Advanced Boomer - Explode willingly, dealing blast damage and infecting nearby humans - 1,000,000 XP. // Yep, SeV. It's worth it.
____________________________________________
Recapitulation of the classes.

Default Zombie - Standart Infect (-3HP) - 0 XP
Mutated Zombie - Infect (-5 HP), Drunk vision - 500 XP //
Hunter Zombie - High jump - 3000 XP // Nothing changed, this class is good enough.
Witch Zombie - -40 HP - 5000 XP // It's a pretty shit class for 10,000 XP.
Heavy Zombie - Has 200 HP - 7500 XP //
Reaper Zombie - Chainsaw with increased damage, 10,000 XP. //
Boomer Zombie - 20,000 XP - Explodes and infects on death - Has 50 HP only //
Tank Zombie - 27,500 XP - Throw everyone around, -5 HP
Rogue Zombie - 35,000 XP - Has a human skin and a human color //
Knife Zombie - 45,000 XP - Knife that deals critical damage //
Advanced Mutated - 65,000 XP / Infect all around (-5 HP) //
Heavy Screamer - Throw all around, -5 HP to humans, 75,000 XP //
Flesh Eater - Infect (Drunk & -10 HP), 100,000 XP // It's good enough, don't change anything.
Burning Zombie - Set those who are around you on fire, 150,000 XP. //
Ghost Zombie - Can "Possess" one human, turning him into a Zombie. Can be used once every 3 minutes // 200,000 XP
Advanced Screamer - Throw all around, +10 HP to Zombie and -15 HP to Human - 250,000 XP //
Radioactive Zombie - Flesh-melting infection, -20HP per second. // 350,000 XP
Advanced Witch - -75 HP Damage - 400,000 XP //
Advanced Tank - Throw all around you, -20 HP. 600,000 XP //
Burning Ashes - Explode what's in front of you, dealing blast damage only. // 850,000 XP.
Spitter Zombie - Infect all around you, -20 HP/S. // 950,000 XP.
Advanced Boomer - Explode willingly, dealing blast damage and infecting nearby humans // 1,000,000 XP.

Those who are in bold are new classes.

Noticed something off about the witch zombie.
40 HP is enough, because it also infects.

And now, for the Rank Classes.

Hopper Zombie - Rank 5 - Double high jump // An improved version of the "Hunter zombie"

Skin ID: 4
Health: 100
Weapon: Fists
Armor: 0
Skill: Ability to mega-jump twice.

Screamer Zombie - Rank 15 // Nothing changes

Napalm Zombie - Rank 25 // Explodes on death and sets everything around on fire. (Two explosions, ID 0 and ID 1)

Skin ID: 22
Health: 100
Armor: 0
Weapon: Fists
Skill: Explodes on death, dealing physical and fire damage. (Create two explosions after death, ID 0 and ID 1)

Nemesis - Rank 30 // Well, it's balanced?!

I guess that also works. Reduce cooldown to 3 seconds?

So far so good, but perhaps a cure to the campers: a zombie that can either drag you from a long distance to his location, or a zombie who can teleport to your location perhaps?

Quote: Vector wrote in post #7

---

So far so good, but perhaps a cure to the campers: a zombie that can either drag you from a long distance to his location, or a zombie who can teleport to your location perhaps?

---

Quote: [AK]holy123 wrote in post #8

---

Quote: Vector wrote in post #7

---

So far so good, but perhaps a cure to the campers: a zombie that can either drag you from a long distance to his location, or a zombie who can teleport to your location perhaps?

---

Nemesis can do that, so... :L

---

Woah woah woah bro calm down...

I like your creativity.. but there are alot of OP CLASSES here man..

#1 The mutated zombie: Drunk vision? it already has stronger infection so thats enough.

#2 Screamer at rank 15 Hell no brother.. should be like 25 or something like that.. everyone will have this class

#3 The witch 30 Hp is enough.. it would be op AF!

#4 Heavy zombie >>> 150 hp is enough op class for 7500

#5 Boomer .. 25 hp 50 would be hard to kill plus it would be much powerfull if its going to be added make the xp req higher

#6 Rogue zombie... this idea is in all zombie server its cool but its over powered maybe add a button that turns it on and off and the time should be like 15 sec or 20 sec

#7 The Ghost zombie.. might wanna make it (1 Time each round)

#8 Burning zombie... is nice but it will make alot of mess xd

#9 The flesh melting infection i definitely dont support it its a VERY VERY OP class a zombie can just camp and all the humans would die

#10 I dont think we should bring back the Adv boomer its just too powerful

I like most of ur ideas but u have got alot of op classes here especially the Knife Zombie 50 hp? so thats 2 hits for each human almost
Good job.. i like ur creativity :D