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Overview

Welcome to Just Cause 4 Multiplayer!

Get ready to experience Just Cause 4 like never before with full multiplayer support. Whether you want to create your own custom server, develop amazing scripts and resources, or explore the extensive API documentation, you've come to the right place!

What is JC4MP?​

Just Cause 4 Multiplayer (JC4MP) is a complete multiplayer modification for Just Cause 4, bringing chaos, destruction, and adventure to a shared world. Host your own server, customize it with scripts and mods, and invite players from around the globe to join in the fun!

Did You Know?

JC4MP is completely free to download and use, as long as you own Just Cause 4 on Steam. If you're looking to join a server and play with others, download the Just Cause 4 Multiplayer client here. Otherwise, keep reading to learn how to host your own server!

Getting Started​

Ready to dive in? Here's what you can do:

  • 🚀 Set Up Your Server - Follow our Server Setup Guide to get your server running in minutes!
  • ⚙️ Configure Your Server - Learn all about server configuration options in our Server Configuration guide
  • 📜 Add Scripts - Enhance your server with custom scripts using our Adding Scripts tutorial
  • 🤖 Chat with Rico - Need help writing scripts? Visit our Chat with Rico page to learn how to make scripts or even have our AI assistant write scripts for you!
  • 🔧 Explore the API - Dive deep into our comprehensive API documentation for client, server, and shared APIs

What You'll Need​

  • Just Cause 4 installed on Steam
  • Server Files - Download the latest server build for your platform from our Servers page
  • A Server Key - Get your free server key from the JC4MP Server Dashboard
  • Steam Web API Key - Obtain your Steam Web API key from Steam's Developer Portal

Ready to Build Something Amazing?​

Let's get started! Head over to our Server Setup Guide and you'll have your server running in no time. Need help with scripting? Check out our Chat with Rico page - an AI assistant that can help you create scripts for your JC4MP server. The adventure awaits!