How The Addon Functions:

Spawning: The spawn weight for all default zombie types have been increased and other mob types spawn weight have been decreased so you can still get those other drops but you'll mainly have to deal with zombies.

Hordes: When zombies spawn no matter how far they are (as long as they're within render distance) they will start making their way towards you forming large hordes while ensuring not too many spawn lagging your game

Mutations: Zombie mutation accrues every 24 in game days and It will only happen within the 5 times, after that the zombies will be at their final form. Mutations Cause Small increase in the zombies stats creating a fun balanced and challenging experience. Mutations are tied to world age so if added to a preexisting world you may not start with the first tier of zombies depending on how much time you've played the world.

Zombie Drops: Zombies will drop less rotten flesh and occasionally drop more useful items such as arrows, charcoal, chicken, and more. Zombies will have a small chance of dropping a random piece of enchanted iron gear. And a very small chance of dropping random enchanted diamond gear.

Gear: Zombies will have a increased chance of spawning with gear (armor and weapons) and also have a higher chance of spawning with stronger gear such as iron and diamond armor.

Zombie Types:

Mutant Zombie; You all know him, he will spawn very rarely as a boss and unlike the rest of the zombies he will only mutate 3 times

Zombies now have glowing eyes

Charge Zombie: Much less Common than regular zombies the charge zombie is a faster zombie that can climb walls, and when he hits you he'll disorientate you.

Base stats (before mutations):  Health 16 | Attack 5 | Movement 31

Horde Master: Much less Common than regular zombies the Horde Master is a bigger slower but stronger version of a zombie. hits from him can injure your legs making you temporarily move slower

Base Stats (before mutations): Health 100 | Attack 9 | Movement 18

Buff Zombies: Less common than regular zombies the buff zombie is a slightly slower but stronger version than regular zombies.

 Base Stats (before mutations): Health 25 | Attack | 6 Movement 20

Default Zombies: Because of the amount of zombies that spawn and surround you. I had to decrease their base stats to make it more balanced, but as mentioned they will mutate becoming harder to fight off.

Base Stats (before mutations): Heath 13 | Attack 2 | Movement 20

(Updated With Custom Textures)

Great Review By Spyderrock (old/pre-bugfixes)

Extra Additions:

I recommend paying on a new world although adding this addon to a pre-existing world is completely fine, you may just start off with stronger zombies depending on how long you've played the world.

1. Dogs have increased health and damage 🙂
2. The Buff zombie in its final mutation form can climb walls
3. Zombies are very attracted to villagers and traders
4. Some zombies can walk through berry bushes
5. Optional zombie only mode, where the only monsters that can spawn in the overworld are zombies

Please add a link to the addon if using in in a video and don't add your own download link 

Thank you for installing you're free to edit the mod on your own to make changes, just please don't claim it or not give credit 🙂