Hostile Harmony
Ever noticed how pillagers and zombies just ignore each other? Or how a skeleton strolls right past a vindicator like they are old friends? If that has always bugged you, Hostile Harmony is the add-on that finally fixes it. This mod makes hostile mobs genuinely hostile to one another, turning every dark cave, raid, and night stroll into a proper brawl. Illagers versus the undead, piglins versus witches, spiders hunting livestock, and creepers creeping on villagers. It is the chaos Minecraft should have shipped with from the start.
What Hostile Harmony Changes
At its core, Hostile Harmony rewrites mob relationships so factions actually behave like factions. Illagers now fight other monsters, and those monsters fight back. Pillagers, vindicators, evokers, witches, ravagers, vexes, and illusioners all target zombies, skeletons, slimes, piglins, blazes, ghasts, and basically every other hostile mob you can think of.
No more friendly fire between illagers either. Pillagers constantly shooting each other during raids was ridiculous, and now their crossbow bolts do not damage their allies. Mobs also fear the Warden. Instead of mindlessly wandering toward certain death, living mobs flee when they spot one, while the undead simply do not care because they have no survival instincts to speak of. Villagers run from Endermen, which makes perfect sense, while illagers and Endermen quietly ignore each other. Call it a truce, call it mutual respect, call it whatever you like.
Spider Update: Predators at Last
Spiders and cave spiders now hunt small animals such as rabbits, chickens, foxes, cats, sheep, pigs, frogs, and armadillos. If it is small and does not fly, it is on the menu. Their bites inflict poison, prey animals flee when a spider approaches, and villagers wisely run too. Wolves, however, will stand and fight, because of course they will. Pillagers attack spiders as well, since they now attack everything.
Raid, Slime, and Mooshroom Updates
Creepers now target villagers as well as players, and iron golems can target creepers to defend them. Witches act as healers for illager raiding parties, throwing Instant Health II splash potions at injured allies within an eight-block support range. Slimes attack anything with zero self-preservation, can consume dropped meat, and optionally grow when they do. Later updates added configurable mooshroom behavior, including mycelium regrowth, mushroom drops on death, and red mooshrooms that turn aggressive and inflict poison and nausea when attacked.
Supported Versions and Loader
Hostile Harmony is built for Minecraft 1.20.1 on Forge 47.4.16 or newer, and it requires Java 17. The final update also fixed illagers abandoning a fight the moment a player came into view, so they now finish what they started. If you are setting up a modded world, the foxygame.net launcher can install Hostile Harmony in a single click, keeping the correct Forge build and Java version paired automatically so you skip the usual setup headaches entirely.
How to Install Hostile Harmony
Getting started is straightforward for anyone comfortable with Forge mods.
- Install Forge 47.4.16 or newer for Minecraft 1.20.1 and run the game once.
- Download Hostile Harmony for Minecraft from your preferred mod source.
- Drop the jar file into your mods folder.
- Launch the Forge profile and confirm the mod loads on the title screen.
Once loaded, most AI changes can be individually enabled or disabled through the config, with whitelist and blacklist support for targeting behaviors. Raids get a lot more interesting when a zombie horde shows up, just saying.
Building Addons with Datapacks
Hostile Harmony's mob relationships are driven by a datapack-friendly registry, so you can extend or trim them without writing code. Place a JSON file anywhere under data/<your_namespace>/mob_relationships/<name>.json, and it merges on top of the built-in defaults. Files reprocess every time datapacks reload, though mobs already spawned keep their original AI goals until new ones appear.
Groups include illager_types, hostile_to_illagers, undead_types, spider_prey, flee_from_spiders, spider_poisonable, slime_friends, and witch_heal_targets. Each entry uses a group, an add or remove action, and an array of entity IDs. Unknown IDs are skipped with a log warning, so shipping an addon that references optional mods is safe. A worked example is bundled at data/hostileharmony/mob_relationships/example_addon.json, and the spider_extra_prey config option lets you add prey without a datapack at all.
If you want unpredictable, living battlefields where every monster has an opinion about every other monster, Hostile Harmony delivers exactly that. Grab it, tweak the config to taste, and watch your next raid descend into glorious anarchy.