Requirements

Before installing Better Ecology, ensure your system meets these requirements:

Installation Steps

Follow these steps to install Better Ecology on your Minecraft client or server.

Step 1: Install Fabric Loader

The Fabric Loader enables mods to run on Minecraft.

1. Visit fabricmc.net/use/  and download the Fabric installer
2. Run the installer executable
3. Select Minecraft 1.21.1 from the version dropdown
4. Choose your installation directory (usually auto-detected)
5. Click Install and wait for completion
6. Close the installer when it shows “Successfully installed”

Verify installation: Launch Minecraft and check that a “Fabric” profile appears in the launcher.

Step 2: Download Required Mods

You need to download two JAR files:

Fabric API (Required dependency):

1. Visit modrinth.com/mod/fabric-api 
2. Click the Versions tab
3. Download the latest version for Minecraft 1.21.1
4. Save the file (named like fabric-api-0.100.0+1.21.1.jar)

Better Ecology:

1. Visit the Better Ecology releases page 
2. Download the latest .jar file for version 1.21.1
3. Save the file (named like better-ecology-1.0.0+1.21.1.jar)

Step 3: Install the Mods

Locate your Minecraft folder:

# Windows
C:\Users\<YourUsername>\AppData\Roaming\.minecraft
 
# macOS
/Users/<YourUsername>/Library/Application Support/minecraft
 
# Linux
/home/<YourUsername>/.minecraft

Install the JAR files:

1. Navigate to your Minecraft folder
2. Open the mods folder
   • If the folder does not exist, create it manually
3. Copy both JAR files into the mods folder:
   • fabric-api-*.jar
   • better-ecology-*.jar

Your mods folder should now contain at least these two files.

Step 4: Launch the Game

1. Open the Minecraft Launcher
2. Select the Fabric profile from the dropdown
3. Click Play
4. Wait for Minecraft to load

The mod will initialize during the loading screen. Check the game logs for confirmation.

Verifying Installation

Once in-game, you can verify the mod is working by observing enhanced animal behaviors.

Visual Verification

Open a creative world and spawn some animals to test:

# Spawn test animals
/summon minecraft:sheep ~ ~ ~
/summon minecraft:pig ~ ~2 ~
/summon minecraft:cow ~ ~4 ~

What to look for:

1. Sheep will search for grass blocks and lower their heads to graze
2. Pigs will periodically root in the ground, creating particle effects
3. Chickens will peck at the ground and search for seeds
4. Groups of animals will maintain cohesion and avoid crowding each other

Command Verification

Use the debug command to inspect animal data:

# Check hunger and thirst values
/debugeco hunger @e[type=sheep,limit=1,sort=nearest]
/debugeco thirst @e[type=cow,limit=1,sort=nearest]

If the command works and returns values, the mod is properly installed.

Log Verification

Check the game logs for the initialization message:

[Better Ecology] Better Ecology initialized
[Better Ecology] Registered hunger attachment
[Better Ecology] Registered thirst attachment

Troubleshooting

Mod Not Loading

Symptoms: No behavior changes, mod does not appear in mod menu

Solutions:

1. Verify you are using exactly Minecraft 1.21.1 (not 1.21 or 1.21.2)
2. Check that Fabric Loader appears in the launcher profile dropdown
3. Confirm both JAR files are in the mods folder (use F3 to check paths)
4. Ensure you downloaded the correct Fabric API version for 1.21.1

Check the mods folder:

# The mods folder should contain:
mods/
  fabric-api-0.100.0+1.21.1.jar
  better-ecology-1.0.0+1.21.1.jar

Game Crashes on Startup

Symptoms: Minecraft crashes before reaching the main menu

Solutions:

1. Verify you have Java 21 or newer installed:

   java -version
   # Should show version 21 or higher

2. Check for incompatible mods (remove other mods temporarily to test)
3. Review the crash log in logs/latest.log for specific errors
4. Look for error messages mentioning “better-ecology” or “attachment”

Common crash causes:

• Java version too old (Java 17 or earlier will not work)
• Conflicting mods that modify animal AI
• Corrupted JAR file (try re-downloading)

Behaviors Not Working

Symptoms: Mod loads but animals behave normally

Solutions:

1. Run /reload to refresh data pack configurations
2. Check that entities were spawned after mod installation
   • Pre-existing entities may not have mod data attached
   • Spawn new entities with /summon or spawn eggs
3. Verify the animal is supported (see Animal Overview)
4. Check server logs for warnings about missing configuration files

Incompatible Mods

The following mod types may conflict with Better Ecology:

• AI overhaul mods that modify mob goals (may cause conflicts)
• Entity attribute mods that change movement speed or health
• Data pack mods that replace vanilla animal behaviors

If you experience issues, try disabling these mods temporarily to isolate the problem.

Server Installation

Better Ecology works on both single-player and multiplayer servers.

Server Setup (Step-by-Step)

1. Install Fabric on the server:

   • Download the Fabric Server Launcher from fabricmc.net 
   • Run the installer and select your server directory
   • Select Minecraft 1.21.1 and click Install

2. Add the mods:

   # Place in the server's mods folder:
   server/
     mods/
       fabric-api-*.jar
       better-ecology-*.jar

3. Configure the server:

   • Configuration files will be auto-generated in config/better-ecology/
   • See Configuration Guide for customization

4. Start the server:

   # Use the Fabric server launcher
   java -jar fabric-server-launch.jar

Client Requirements

Important: All players connecting to the server must install Better Ecology on their client for the full experience.

• Without the client mod, behaviors will still work server-side
• Players will miss visual feedback like grazing animations and particles
• Hunger/thirst HUD overlay requires the client mod

Hot-Reloading on Servers

Server administrators can modify configurations without restarting:

# After editing config files, run:
/reload

This reloads all data packs and applies new behavior parameters immediately.

Next Steps

Now that Better Ecology is installed, you can:

1. Learn about configuration: Read the Configuration Guide
2. Explore animal behaviors: Check the Animal Overview
3. Understand the science: See Research Documentation
4. Customize behaviors: Learn about the Behavior System