Hostile Harmony

Hostile Harmony

Ever noticed how pillagers and zombies just… ignore each other? Or how a skeleton will walk right past a vindicator like they're old friends? Yeah, that's always bugged me too. This mod makes hostile mobs actually hostile to each other. Illagers vs the undead. Piglins vs witches. The chaos Minecraft should've had from the start.

What This Mod Does

Illagers now fight other monsters. Pillagers, vindicators, evokers, witches, ravagers, vexes, and illusioners will all target zombies, skeletons, slimes, piglins, blazes, ghasts, and pretty much every other hostile mob. And those mobs fight back. No more friendly fire between illagers. Pillagers constantly shooting each other during raids was ridiculous. Now their crossbow bolts don't damage their allies. Mobs actually fear the Warden. Instead of mindlessly wandering towards their death, living mobs will flee when they spot a Warden. Undead don't care though - they're too braindead to have survival instincts. Villagers run from Endermen. Makes sense, right? Those things are terrifying. Illagers and Endermen ignore each other. Call it a truce, call it mutual respect, call it whatever. They just don't bother with each other. Skeletons are squishier. Regular skeletons and strays have 3 hearts instead of 10. Wither skeletons have 4. They're ranged mobs, they shouldn't be tanks.

The Spider Update (v1.0.1)

Spiders are now proper predators. Spiders and cave spiders hunt small animals - rabbits, chickens, foxes, cats, sheep, pigs, frogs, and armadillos. If it's small and doesn't fly, it's on the menu.

Venomous bites. Spider attacks now poison their prey. Those fangs aren't just for show anymore.

Prey animals flee from spiders. Rabbits are the most paranoid (14 blocks), foxes are alert (12 blocks), and the rest notice at about 10 blocks. Except wolves - those idiots will stand and fight.

Villagers fear spiders. They'll run when they spot one nearby. Smart.

Pillagers attack spiders. Because of course they do. They attack everything now.

The Raid Update (v1.0.2)

Creeping up on more. Creepers now target villagers as well as players Iron golems can now target creepers to defend villagers

Bewitched. Witches now act as healers for illager raiding parties. Witches throw Instant Health II splash potions in an 8 block support range at injured allies (below 60% health) and affects Pillagers, Vindicators, Evokers, Illusioners, Ravagers, and Vexes

The Slime Update (v1.0.3)

• Slimes attack anything and have no preservation instinct
• Slimes can now consume dropped meat items
• Optional slime growth mechanic when consuming items
• QoL Changes & Bug Fixes:
  • Added extensive configuration support for mob AI and gameplay changes
  • Most AI changes can now be individually enabled or disabled
  • Added whitelist/blacklist support for mob targeting behaviors
  • Added support for configuring modded entities as hostile, friendly, or prey
  • Added datapack-friendly entity relationship configuration system
  • Illager hostility towards hostile mobs is now configurable
  • Skeleton stat changes can now be disabled
  • Improved support for addon mods and datapack extensions

The Final Update (v1.0.4)

• Added in Mooshroom behaviour mechanics (configurable)
  • Shearing mooshrooms no longer converts them to cows
  • Mooshrooms eat mycelium to regrow mushrooms, or a 2 min timer (config setting)
  • Mooshrooms drop mushrooms on death
  • Brown and red mooshrooms maintain their variant when sheared
  • Red mooshrooms now become aggressive when attacked
  • They chase and attack the player who hurt them
  • Attacks inflict poison and nausea effects
  • Aggression lasts 10 seconds (configurable)

Just One More (v1.1.0)

• Fixed illagers abandoning a fight with a hostile mob the moment a player came into view, instead of finishing the fight they were already in
• Added a worked datapack example showing how to make modded mobs hostile to illagers (hostile_to_illagers group)

Requires

• Minecraft 1.20.1
• Forge 47.4.16+
• Java 17

Known Interactions

Raids get a lot more interesting when a zombie horde shows up. Just saying.

Creating Addons

Hostile Harmony's mob relationships (who's an illager, who hunts who, who's afraid of what, etc.) are driven by a datapack-friendly registry, so you can extend or trim them without a datapack of your own becoming required. All you need to do is just drop a JSON file in, no coding needed. This works great for adding modded animals/mobs to the system, or tweaking the defaults for your pack.

How it works

Place a JSON file anywhere under:

data/<your_namespace>/mob_relationships/<name>.json

Any number of files, from any datapack or mod, are merged together on top of Hostile Harmony's built-in defaults. They're reprocessed every time datapacks reload (world join, /reload), so changes take effect without restarting. However, mobs that already exist in the world keep whatever AI goals they were given when they spawned; a /reload only affects new spawns from then on.

File format

{
  "entries": [
    {
      "group": "spider_prey",
      "action": "add",
      "entities": [
        "dragns_livestock:angus_cow",
        "dragns_livestock:merino_sheep"
      ]
    }
  ]
}

• group - which relationship list to modify (see table below). Case-insensitive.
• action - "add" or "remove".
• entities - an array of entity type IDs (<namespace>:<path>), e.g. "minecraft:wolf" or "mymod:beast".

You can include as many entries as you like in one file, mixing groups and actions freely.

Available groups

Group	Effect
illager_types	Treated as an illager and is immune to illager friendly fire, hunted by hostile mobs, healed by witches
hostile_to_illagers	Actively targets and attacks illager-type entities
undead_types	Undead mobs and ignores the Warden-avoidance flee goal
spider_prey	Actively hunted by spiders and cave spiders
flee_from_spiders	Flees when a spider gets close (usually a subset of spider_prey)
spider_poisonable	Receives Poison I when hit by a regular spider
slime_friends	Slimes and magma cubes will not target these
witch_heal_targets	Witches will throw healing potions at these when they're low on health

Example

{
  "entries": [
    {
      "group": "spider_prey",
      "action": "add",
      "entities": ["dragns_livestock:angus_cow", "dragns_livestock:merino_sheep"]
    },
    {
      "group": "flee_from_spiders",
      "action": "add",
      "entities": ["dragns_livestock:angus_cow", "dragns_livestock:merino_sheep"]
    },
    {
      "group": "illager_types",
      "action": "add",
      "entities": ["mymod:custom_illager"]
    },
    {
      "group": "hostile_to_illagers",
      "action": "add",
      "entities": ["mymod:custom_hostile_mob"]
    },
    {
      "group": "spider_prey",
      "action": "remove",
      "entities": ["minecraft:wolf"]
    }
  ]
}

This adds two modded animals as spider prey that also flee from spiders, adds a custom illager to the illager faction, makes a custom modded hostile mob attack illagers, and removes wolves from the default spider prey list.

Notes

• Unknown entity IDs (e.g. from a mod that isn't installed) are skipped with a warning in the log, and it is safe to ship an addon that references optional mods.
• Files are processed alphabetically, so if two files touch the same group, the later one wins for anything they both mention.
• Need to add prey entries without shipping a datapack at all? The spider_extra_prey config option accepts a plain list of entity IDs directly in the config file. This is handy for quick single-player tweaks.
• A worked example is bundled with the mod at data/hostileharmony/mob_relationships/example_addon.json if you want a template to start from.

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Questions, bugs, suggestions? Drop them in the comments.