Introduction · What is an online multiplayer RPG?
15 minTwo words, two ideas. Understand both and the whole project makes sense.
RPG — you are somebody, and you grow
In a role-playing game you take on a character. That character has stats — numbers like health, attack and defence. It has skills it can use, and an inventory of things it carries.
The heart of an RPG is progression. You fight, you earn experience, you level up, you get stronger. Then harder enemies become fair fights.
Online multiplayer — one world, several computers
Each player runs the game on their own machine. One machine is the server, and it decides what is true. The others are clients, and they ask the server what happened.
Almost nothing is actually sent. No pictures, no sounds, no walls. Only small facts travel: who joined, which character they picked, where they are standing.
Why that is hard
Messages take time to arrive. While a message is travelling, the world has already moved on. Every multiplayer game is a clever answer to that one problem.
The one rule to remember
Every machine runs the same code and builds the same world. Keep asking: can this be worked out locally instead of sent? Sending everything always works, and always gets slow.
Go and look at some of these
None of these are about our engine. They are about the ideas, and the ideas are the same everywhere. Watch or read at least one from each of the first two groups.
🌐 How online multiplayer works
- How Multiplayer Games Work — Nick Maltbie. A clear tour of clients, servers and what actually travels.
- Client-Server Game Architecture — Gabriel Gambetta. To read, with little playable diagrams. The classic explanation.
- Search words if a link has moved: how multiplayer games work client server explained.
⚔️ How RPG systems are designed
- What Makes a Good Level Up System? — Design Doc. Why some levelling feels great and some feels like a chore.
- Make Your First RPG · Levelling Up & XP Progression — GameMaker. A different engine, the same maths.
- Search words: RPG levelling system design experience curve.
🎮 A peek at multiplayer in Godot
- How to start making multiplayer games in Godot 4 — CyberPotato. A tiny two-player game, start to finish.
- Godot 4 Multiplayer Tutorial, Part 1 — Gwizz.
- High-level multiplayer — the official Godot documentation. Skim it now; you will build all of it by lesson 21.
Watching is not the lesson. Write down three things you did not know as you go, and keep them at the top of the plan you are about to write.
Basic · The plan
25 minYou are building: the plan for the whole game — what a player will be able to do, and what you as the developer have to make. One document, kept in the project folder, edited all the way to lesson 24.
1 · What the player gets
This is the game from the outside. Copy the list, then add your own detail to every line.
- Register and log in. A screen to make an account and come back to it later.
- Choose a character. A select screen showing each one, with its own look and description.
- A stats and skills page. Health, attack, defence, speed — and the skills that character can use.
- An inventory page. What the player is carrying, and what they have equipped.
- Online multiplayer. Host a world or join a friend's, and play in it together.
- Upgrade the character. Earn experience, level up, spend points on stats or skills.
- Saved progress. Player and character data kept, so next time you carry on where you stopped.
- Choose a map to fight in. Several places, each with its own look and its own monsters.
2 · What you have to make
This is the same game from the inside — your job list. It is longer than the player's list, and that is normal.
- Design the characters. Each one modelled, animated, and given stats that suit it.
- Design the maps. Different places to fight in, each with its own mobs.
- Define the mobs. What they look like, how much health, how hard they hit, how they behave.
- Define a boss for each map. Stronger, with something that makes it different — not simply a bigger monster.
- Define the skills. What each one does, what it costs, and how long before it can be used again.
- Decide what gets saved, and what the server must be in charge of.
A plan is not a promise to build it all at once
Lessons 2 to 24 build the foundation: the world, the characters, the camera, the screens and the connection. Stats, skills, mobs and bosses are designed now and built on top of it afterwards. Plan the whole thing; build it in order.
3 · Draft your extra ideas
Every good game has something the list above does not describe. Add a section called Extra ideas and write at least three. Anything is allowed at this stage.
Some prompts, if you are stuck:
- Can two players do something together that neither can do alone?
- Is there a reason to go back to a map you have already beaten?
- What can a player show off to a friend?
- What happens when a player loses a fight?
- Is there anything in the world that is not a fight?
4 · Write it up
- Open a document called My 3D RPG — game plan. Keep it in the project folder.
- Start with one sentence about what a player does. Example: “Two friends clear a ruined tower, one floor at a time.”
- Add the two lists above, with your own detail on every line.
- Name three characters and two maps, with one line about each.
- Add your Extra ideas section.
Done when: your plan names three characters, two maps, at least one boss, and three extra ideas — and every line of both lists says something about your game, not just the list above.
Challenge 1 · Your player model 🟢 Easy
20 min in classEvery character in your plan needs a body. Get one player character ready. Two routes — pick either, and nobody will mind which.
Route A · Find a free model
Fastest, and completely respectable. Professionals do this every day.
Where to look
- Kenney — clean, simple, free to use for anything.
- Quaternius — free low-poly characters and monsters, already rigged.
- Mixamo — free characters, and the animations for Challenge 3.
- Sketchfab free models — huge. Check each model's licence before you use it.
Route B · Make your own
🟦 Tinkercad — easiest start, in a browser
- tinkercad.com — build a character out of simple shapes, then export it.
- Tinkercad Basics — Build 3D Models — Wize Computing Academy.
- TinkerCAD in 10 minutes — Skills Factory.
🟧 Blender — harder, and far more powerful
- blender.org — free, and what most of the industry uses.
- Create a Low Poly Person — Grant Abbitt. Follow it exactly the first time.
Export as glTF, and write down where it came from
Save or export your character as .glb or .gltf. Godot imports those natively. Keep a list of every model, its author and its licence — you will need it when you show the game.
Done when: you have one player character as a .glb or .gltf file, stored in your project folder, with its source and licence written down.
Challenge 2 · A mob model 🟡 Medium
20 min in classA world with nothing in it to fight is a walking simulator. Make or find one mob — a monster that lives on one of your maps.
Same two routes as Challenge 1. Same file format.
What makes a good first mob
- Readable at a distance. A player must know what it is before it reaches them.
- Clearly not a player. Different shape, different colours. Nobody should attack a friend by mistake.
- Simple. A blob with eyes beats a masterpiece you never finish.
- It fits its map. A tower mob and a forest mob should not look interchangeable.
Then write its card in your plan document:
Done when: one mob model is exported, and its card is in your plan with all five rows filled in.
Challenge 3 · Make it walk 🟠 Harder
25 minA model that never moves is a statue. Give your player character a walk animation.
Route A · Mixamo, the fast way
- Go to mixamo.com and sign in with a free account.
- Upload Character and give it your model.
- The auto-rigger asks you to place a few markers — chin, wrists, elbows, knees, groin. Take your time here.
- Search the animation list for walk and pick one you like.
- Download as FBX, then convert to glTF in Blender. Or download the whole character with the animation included.
If you get stuck
- Rig any Character with the Mixamo Auto-Rigger — Nik Kottmann.
- How to Use Mixamo Animations in Blender — MK Graphics. For getting it back out as glTF.
- Search words: Mixamo auto rig animate character glTF Blender.
Route B · Blender, the honest way
Rig your model with an armature, then key three or four poses in the Dope Sheet. It is slower and you learn far more. Ask your teacher before choosing this in class time.
Then check the name
Write down the clip name exactly
Every animation has a name inside the file, and it is rarely what you expect — Walking, not walk. In lesson 6 you will type these names into a character resource, and a name that is one letter out simply never plays.
Done when: your character has a walk animation, the file is exported as glTF, and the exact clip name is written in your notes.
Extra · The full animation set 🔴 Open-ended
no limitA character needs more than a walk. Add the other three the game will ask for in lesson 12:
- Idle — standing still, but alive. Breathing, shifting weight, looking round.
- Running — clearly faster than the walk, not just the walk sped up.
- Jumping — the push off the ground.
Mixamo has all three, and they will already fit your rigged character. Keep every clip name in the same notes.
If you want to go further
- Add a falling clip too. Lesson 12 has a slot for it, and a jump without a fall looks odd.
- Animate your mob as well — even a slow bob makes a monster feel alive.
- Make all three of your characters, so the select screen in lesson 14 has a real cast.
- Try an attack clip. Nothing uses it yet; it is waiting for when you build combat.
- Watch your idle loop twenty times in a row. Can you see where it joins? Good loops hide the seam.