How to build a multiplayer game with unity

build multiplayer game with unity
April 11, 2025
4 min read
By Cojocaru David & ChatGPT

Table of Contents

This is a list of all the sections in this post. Click on any of them to jump to that section.

index

How to Build a Multiplayer Game in Unity: A Step-by-Step Guide

Want to build a multiplayer game in Unity? This step-by-step guide walks you through the entire process—from setting up your project to optimizing performance—using Unity’s powerful networking tools like Netcode for GameObjects (NGO). Whether you’re creating a fast-paced shooter or a cooperative adventure, this tutorial will help you bring your multiplayer vision to life.

Why Unity Is the Best Choice for Multiplayer Games

Unity dominates multiplayer game development thanks to its cross-platform support, built-in networking tools, and thriving community. Here’s why it stands out:

  • Cross-Platform Play: Deploy your game on PC, mobile, and consoles with minimal extra work.
  • Built-in Networking: Simplify synchronization, player management, and RPCs with Unity’s Netcode for GameObjects.
  • Scalability: Design for small groups or massive online worlds using Unity’s flexible architecture.
  • Asset Store: Speed up development with pre-built assets, scripts, and plugins.

“Multiplayer games thrive on interaction—focus on creating seamless, engaging experiences that keep players coming back.”

Setting Up Your Unity Multiplayer Project

Before diving into networking, set up your project correctly:

  1. Install Unity Hub & LTS Version: Use the latest Long-Term Support (LTS) version for stability.
  2. Create a New Project: Choose 3D or 2D based on your game’s style.
  3. Import Netcode for GameObjects: Add this package via the Package Manager for essential networking features.

Keep your project organized with folders for scripts, assets, and scenes to streamline development.

Implementing Multiplayer Networking with Netcode

Step 1: Install Netcode for GameObjects

Go to Window > Package Manager, search for “Netcode for GameObjects,” and install it. This package handles player synchronization, RPCs, and server-client communication.

Step 2: Configure the NetworkManager

Add a NetworkManager component to an empty GameObject. Set the transport protocol (e.g., UDP) and adjust connection settings.

Step 3: Design Player Prefabs

Create a player prefab with a NetworkObject component. Scripts should inherit from NetworkBehaviour (not MonoBehaviour) for network-aware behavior.

Step 4: Sync Data & Use RPCs

  • Use NetworkVariable<T> for automatic data syncing (e.g., health, score).
  • Implement RPCs for real-time actions:
[ServerRpc]  
void ShootServerRpc() {  
    // Server handles shooting logic  
}  
 
[ClientRpc]  
void PlaySoundClientRpc() {  
    // Clients play sound effects  
}

Testing Your Multiplayer Game

  • Use ParrelSync: Test locally by simulating multiple players on one machine.
  • Host & Join Sessions: Verify connectivity, lag, and synchronization.
  • Monitor Performance: Check network traffic in the Profiler (Window > Profiler) to spot bottlenecks.

Fix issues like desynchronization early to ensure smooth gameplay.

Optimizing Multiplayer Performance

  • Reduce Bandwidth: Sync only essential data and compress network packets.
  • Client-Side Prediction: Mask latency for responsive controls.
  • Object Pooling: Reuse objects (e.g., bullets) to minimize garbage collection.
  • Simplify Scenes: Lower render complexity for better performance.

Publishing Your Multiplayer Game

  1. Pick a Hosting Solution: Use Unity Relay, cloud servers, or dedicated hosting.
  2. Run a Beta Test: Gather feedback from a small player group.
  3. Launch on Platforms: Publish on Steam, itch.io, or app stores.

#multiplayer #gamedev #unity #indiedev #networking