Alex's Mobs — a mod that adds a huge number of new animals and creatures to Minecraft
- Version the article was written on: 1.20.1
- Supported Minecraft versions: 1.16.5 – 1.20.1
- Dependencies: Citadel
Version the article was written on: 1.20.1
Supported Minecraft versions: 1.16.5 – 1.20.1
Dependencies: Citadel
Alex's Mobs adds 89 new mobs to Minecraft — from real animals to fantasy creatures. In vanilla, most biomes have 2–3 passive mobs and look empty even in newly generated worlds. This mod fixes that: each animal is tied to a specific environment and brings its own mechanics — there are no purely decorative mobs here.
Animals of the mod
Most of the mobs are real animals tied to specific biomes. Raccoons, crows, and grizzly bears appear in forests; gorillas, capuchin monkeys, and toucans in jungles; anacondas, caimans, and catfish in swamps; orcas and seals in cold oceans; rattlesnakes and jerboas in deserts.
A gorilla with a baby in a jungle
Fantasy creatures inhabit more dangerous locations. The Bone Serpent leaps out of lava in the Nether and dive-bombs the player from above. The Lavithan swims in lava lakes and can carry up to four players on its back. The Endergrade flies around the End — it can be ridden with a saddle and chorus fruit on a stick.
A special mention goes to the boss — the Void Worm. It does not spawn naturally: it is summoned using the Mysterious Worm item exclusively in the End dimension. Its default health is 160 points.
Behavior and interaction with the world
Some mobs actively interact with the game environment outside the combat system. A raccoon steals food from chests in structures, while a crow plucks crops from farmlands. A seagull snatches food right out of your hotbar slots — you can stop what it can steal via the seagullStealingBlacklist in the config.
GIF: A seagull snatching a fish from the player's hotbar in a coastal biome
The catfish in swamps swallows live mobs smaller than one block and holds them inside until it receives a sea pickle or takes a hit. A cachalot whale, when enraged, destroys wooden blocks around it. The Mungus in the Nether gradually transforms blocks and even the chunk's biome itself depending on the type of mushroom growing on its back — this behavior is regulated by the mungusBiomeTransformationType parameter.
Vanilla mobs also react to their new neighbors: wolves chase moose, polar bears attack seals, cats and foxes hunt jerboas, and spiders attack flies. All these interactions are enabled by default and can be disabled by separate parameters in the config.
A cachalot whale in the open sea
Items and crafting
Upon first entering the world, the player receives the Animal Dictionary — a book containing descriptions of every mob and hints about their drops. If lost, it can be crafted from a regular book, green dye, and any item from the mod. Receiving it at the start is toggled by the giveBookOnStartup parameter.
The opened Animal Dictionary on its main page
Transmutation Table
A craftable block. You place any stackable item in the green slot — the table offers three output options. Each operation costs 3 experience levels. Destroying the table results in an explosion and drops a Nether Star.
The pool of results learns: the more often a certain item is transmuted, the higher its chance to appear again. The balance is adjusted via transmutingWeightAddStep and transmutingWeightRemoveStep — the second parameter should be higher to avoid looping on a single item.
The Transmutation Table with its interface showing three output options
Config
The file is alexsmobs.toml. The [spawning] section contains two parameters for each of the 89 mobs: SpawnWeight (weight in the biome pool, 0 = disabled) and SpawnRolls (an additional 1 in N roll before spawning, 0 = without it). All spawn parameters can be changed independently for each animal.
The [uniqueSpawning] section sets special conditions for specific mobs: The Devil's Hole Pupfish spawns by default in only one single chunk in the entire world — restrictPupfishSpawns = true. Skelewag — only in Shipwrecks, Underminer — in Mineshafts, Farseer — near the world border. The distance from the border is set by farseerBorderSpawnDistance (default is 100 blocks). A cachalot whale can beach itself during a thunderstorm once a day — beachedCachalotWhales = true.
Below are the parameters of the [general] section that affect key mechanics:
| Parameter | What it does |
| giveBookOnStartup | If false — the Animal Dictionary is not automatically given to the player. |
| lavaVisionOpacity | Lava opacity under the effect of a Lava Vision potion. Range: 0.01–1.0. Less = more transparent. |
| shadersCompat | If true — disables some potion effects for shader compatibility. |
| neutralBoneSerpents | If true — the Bone Serpent only attacks in retaliation. |
| mimicubeSpawnInEndCity | If false — the Mimicube spawns according to its own biome config, not just in the End City. |
| mimicreamRepair | If false — item duplication via Mimicream is disabled. |
| raccoonStealFromChests | If false — raccoons do not steal from chests. |
| crowsStealCrops | If false — crows do not pluck crops from farmlands. |
| seagullStealing | If false — seagulls do not snatch food from the hotbar. |
| mungusBiomeTransformationType | 0 — Mungus transforms nothing. 1 — transforms chunk blocks. 2 — transforms both blocks and the biome itself. |
| cachalotDestruction | If false — an enraged cachalot whale does not destroy wooden blocks. |
| cachalotVolume | Cachalot whale sound volume (0.0–10.0). Lower it if the sounds are too loud. |
| leafcutterAntColonySize | Maximum number of ants in a single anthill (2–100000). |
| leafcutterAntBreakLeavesChance | Chance (0.0–1.0) that an ant will break a leaf block. 0.0 — blocks are not broken. |
| falconryTeleportsBack | If true — a tamed eagle teleports back to its owner if it gets stuck. Useful when using OptiFine. |
| voidWormMaxHealth | Maximum health of the Void Worm (0.0–1000000.0). |
| voidWormSummonable | If false — summoning the boss via the item is disabled. |
| transmutingTableExplodes | If false — the Transmutation Table breaks without an explosion. |
| transmutingExperienceCost | Experience levels per single transmutation (0–100000). |
| addLootToChests | If false — mod items are not added to structure loot chests. |
| underminerDisappearDistance | Distance (in blocks) at which the Underminer disappears from the player (1.0–10000.0). |
| pathfindingThreads | Number of CPU threads for pathfinding heavy mobs — elephants, bison, ants, etc. Increase on weak servers (1–100). |
| wanderingTraderOffers | If false — the Wandering Trader does not offer mod items. |
| emuPantsDodgeChance | Chance to dodge a projectile while wearing Emu Leggings (0.0–1.0). 0.45 = 45%. |
If false — the Animal Dictionary is not automatically given to the player.
Lava opacity under the effect of a Lava Vision potion. Range: 0.01–1.0. Less = more transparent.
If true — disables some potion effects for shader compatibility.
If true — the Bone Serpent only attacks in retaliation.
mimicubeSpawnInEndCity
If false — the Mimicube spawns according to its own biome config, not just in the End City.
If false — item duplication via Mimicream is disabled.
raccoonStealFromChests
If false — raccoons do not steal from chests.
If false — crows do not pluck crops from farmlands.
If false — seagulls do not snatch food from the hotbar.
mungusBiomeTransformationType
0 — Mungus transforms nothing. 1 — transforms chunk blocks. 2 — transforms both blocks and the biome itself.
If false — an enraged cachalot whale does not destroy wooden blocks.
Cachalot whale sound volume (0.0–10.0). Lower it if the sounds are too loud.
leafcutterAntColonySize
Maximum number of ants in a single anthill (2–100000).
leafcutterAntBreakLeavesChance
Chance (0.0–1.0) that an ant will break a leaf block. 0.0 — blocks are not broken.
falconryTeleportsBack
If true — a tamed eagle teleports back to its owner if it gets stuck. Useful when using OptiFine.
Maximum health of the Void Worm (0.0–1000000.0).
If false — summoning the boss via the item is disabled.
transmutingTableExplodes
If false — the Transmutation Table breaks without an explosion.
transmutingExperienceCost
Experience levels per single transmutation (0–100000).
If false — mod items are not added to structure loot chests.
underminerDisappearDistance
Distance (in blocks) at which the Underminer disappears from the player (1.0–10000.0).
Number of CPU threads for pathfinding heavy mobs — elephants, bison, ants, etc. Increase on weak servers (1–100).
wanderingTraderOffers
If false — the Wandering Trader does not offer mod items.
Chance to dodge a projectile while wearing Emu Leggings (0.0–1.0). 0.45 = 45%.
Conclusion
Alex's Mobs adds 89 mobs, each with unique drops or behavior, a deep config with precise control over spawning and interactions — making the mod a great foundation for any survival modpack. The main limitation is that the current version has stopped at 1.20.1, with no support for newer Minecraft versions at the moment.
Installation
A typical installation takes about 5 minutes. The flow is the same; only the loader and the matching build differ.
- Install a mod loader (Forge, Fabric or NeoForge) that matches your Minecraft version.
- Download the mod file (.jar) built for that same version.
- Place the .jar into your .minecraft/mods folder.
- Launch Minecraft with the modded profile and check the mod loads in-game.