CrackedZombie Mod 1.12/1.11.2 makes Minecraft zombies a lot more over powered. Zombies in the daytime. Zombies are everywhere, be careful. Sort of an adventure mod. The zombies will attack players, chickens and pigs. There are options in the config file to control spawning of skeletons, creepers, spiders, slime, and endermen. The default minecraft zombies are disabled. There is a GUI configuration screen under the main screen mods button. Select the crackedZombie mod and then the config button. You can enable/disable other mob spawns such as the creepers, skeletons, etc. When spawning the player will be given a random type sword for protection. That option can be disabled in the config if you’re really hard core. The zombies should be able to spawn in any biome derived from the BiomeGenBase class. Zombies should spawn in biomes created by ExtraBiomesXL or Biomes O Plenty for instance.
CrackedZombie Mod
I recommend creating a world with these presets if you want a real zombie apocalypse adventure.
2;7,56x1,5x3,2;6;biome_1,decoration,lake, lava_lake
This is a swamp world similar to Swampcore, only deeper. You can mine ore here. Using the CrackedZombie defaults you will have to contend with many walkers and spiders. Want some bad weather to go along?
/weather thunder 100000
should do it. Oh, and watch out for the witch. With a little luck you can find a witches hut for shelter on your first night.

Screenshots:

Really too many zombies!
CrackedZombie-Mod-1.jpg
Still too many zombies!
CrackedZombie-Mod-2.jpg
CrackedZombie attacking
CrackedZombie-Mod-3.jpg
CrackedZombie
CrackedZombie-Mod-4.jpg
CrackedZombie-Mod-5.jpg

Requires:

Minecraft Forge

How to install:

  1. Make sure you have already installed Minecraft Forge.
  2. Locate the minecraft application folder.
    • On windows open Run from the start menu, type %appdata% and click Run.
    • On mac open finder, hold down ALT and click Go then Library in the top menu bar. Open the folder Application Support and look for Minecraft.
  3. Place the mod you have just downloaded (.jar file) into the Mods folder.
  4. When you launch Minecraft and click the mods button you should now see the mod is installed.

CrackedZombie Mod 1.12/1.11.2 Download Links:

For Minecraft 1.12
Download from Server 1    Link 2