Most multiplayer tutorials stop once two windows can see each other. This starter carries on to the parts that break in a real game. The server decides where everyone is, your own player still moves the moment you press a key, and bad input gets rejected.

This is a full Godot project, not an addon. Installing it from the Project Manager creates a new project with the demo ready to run. To use the system in your own game, copy its folder across; the README explains which files you need.

Features

• Host, join or run a headless dedicated server, for up to 4 players over Godot's built-in ENet.
• A ready-up lobby, timed rounds, and chat with emotes.
• The server owns every player. Clients send their input, never their position.
• Client-side prediction and reconciliation, so your own player responds instantly even with lag.
• Other players are drawn 100 ms in the past, so they move smoothly between updates.
• Every RPC (a function call sent over the network) checks who sent it before it runs.
• Testing tools: a network inspector on F3, a lag dial on F4, and a bot that joins and walks around.

Try it

1. In Godot, open Debug > Customize Run Instances, turn on Enable Multiple Instances and set the count to 2.
2. Give instance 1 the arguments --host --name=Host and instance 2 --join=127.0.0.1 --name=Alex.
3. Press F5. Two windows open, already connected.
4. Click Toggle ready in both windows, then Start round in the host window.
5. Move with WASD, sprint with Shift, and click the chat box to talk.

Compatibility

• Made for Godot 4.7, standard build. GDScript only, no .NET needed.
• Tested on Godot 4.7.2 stable, on Windows, with two local windows and a headless dedicated server. Earlier versions of Godot 4 are untested.
• Renderer: Compatibility.

Known limitations

• A starter, not anti-cheat. Traffic is not encrypted and chat has no rate limit.
• Players join by IP address. There is no lobby browser, relay or NAT punch-through.
• There is no host migration. If the host leaves, the session ends.
• 2D and desktop only. There is no Steam, WebSocket or browser transport.

License

The code is MIT licensed (LICENSE in the project folder). There are no third-party assets: everything is drawn in code or uses Godot's built-in theme.

Learn how it works

CodingQuests has a quest that builds this system step by step, in your browser:

• Two Windows Talking: Starts from zero: host a game, join it, and send your first RPC. Free, 9 lessons.
• RPCs: Who Is Allowed To Say What: Who is allowed to call what: RPC authority and the different RPC modes. Free, 8 lessons.
• Never Trust the Client: Builds this project's validation, so the server checks every request. First 3 lessons free.
• Prediction and Reconciliation: Builds this project's prediction, reconciliation and interpolation. First 3 lessons free.

Source code and issues: https://github.com/CodingQuests/godot-multiplayer-starter