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Headcrabs are a species of alien parasitoids known for latching onto a humanoid head, cracking their skull, and taking control of their bodies.
This addon intends to bring that to Minecraft, with a little bit of originality to spice it up.
Lets start from the beginning.

This is the gonarch, aka "Big Momma". She is a mature female headcrab, and can do some serious damage if you come unprepared! She will use a ranged attack, which spits acid from the top of her body, and will also do a melee attack. Be careful when hiding in a house- She can tear down a LOT of blocks if you make her angry! She will also summon these little guys - 
- Baby headcrabs! They will grow into juvenile headcrabs after rougly 5 minutes of being born. They start small, and grow bigger, and eventually become these guys - 
Standard Headcrabs, or juvenile headcrabs. These guys are where the real fun begins!
Headcrabs can jump at and take over a variety of entities! The list includes -
Players
Villagers
Pillagers
Vindicators
Evokers
Creepers
Witches
Currently, there are no more plans for headcrab zombies, as these are the only logical humanoids that the game has (Endermen and zombies are not logical humanoids).
Here is an example of what the zombies look like - this is a witch variant!
They will attack most passive mobs as well as the humanoids a standard headcrab attacks.
Be careful when attacking them- they can split in two if they take damage! Sometimes, when they die, the headcrab drops from the host, still alive and ready to take over their challenger.
Zombies wouldnt be complete without an evolution process! So, we have - 
-These guys! These are gonomes, the next stage in the life of a headcrab. They are big and burly, and pretty tough! They will attack most passive mobs as well as the humanoids a standard headcrab attacks, like the zombie. Be sure not to try and hide in a wood house- these guys break blocks!
Feasting! A newer feature- Gonomes and zombies will feast on a variety of food items, ranging from plants such as apples and potatoes to meats such as raw beef and rotten flesh! Theres a few mob drops that they eat as well, such as spider eyes and leather.
There's a few more things that I won't cover here, but you'll find easily on your own!
Want updates and leaks on this project, or have suggestions and bugs to report? Join my discord!
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Note: You are more than welcome to showcase this addon, as long as you provide credit/give a link to this page
[DISCLAIMER] Do not upload this to 3rd party websites without my permission/credit.