> ## Documentation Index
> Fetch the complete documentation index at: https://docs.summerengine.com/llms.txt
> Use this file to discover all available pages before exploring further.
# Make your game multiplayer
> How a Summer multiplayer game fits together: one project, a server that owns the rules, and Local Play to test it all on your own machine.
A Summer multiplayer game is **one project with two starting scenes**. The
**client** scene is what every player runs: input, camera, visuals and menus.
The **server** scene runs without a screen and owns the rules: the score, the
doors, who won. Summer runs the server for every match, so no player has to
host, and nobody needs to share an address.
The same code runs on your machine and once the game is published. There's no
separate "server version" to keep in sync, and no local-only shortcuts to
remove later.
## How it fits together
A few words come up on every page in this section:
* **World:** one running match or shared place, run by one server. A
10-minute round is a World, and so is a server that stays up for weeks.
* **Session:** one player's seat in a World. Summer checks who the player is
before they get one, so your server always knows exactly who did what.
* **Queue:** how players find a World, such as "casual" or "ranked 2v2". See
[Match players into games](/build/matchmaking).
## What your players get
* **Instant controls.** Each player's own character responds the moment they
press a key, on any connection. See [Make movement feel instant](/build/movement).
* **A fair game.** The server checks every move and request, so a modified
client can't give itself points, speed or items.
* **Nobody ends the match by leaving.** No player is the host. If someone
quits or drops out, everyone else keeps playing, and a player who reconnects
in time gets their seat back.
* **The same account everywhere.** Players sign in once with their Summer
account, and your game sees their name in every match.
## Start here
Make my Summer project multiplayer. Use the Summer `multiplayer` skill to plan
it and the `multiplayer-project` skill to set it up; if you don't have them
installed, find them in the Summer library.
* Split the game into a client scene every player runs and a server scene that
owns the rules.
* Players join a match from my existing menu.
* Every player sees one character per player who joined.
Read my project first and tell me what moves to the server and what stays on
the client before you change anything. Then run it with Local Play with two
players and tell me what you saw.
Read my Summer project and explain how it would work as a Summer multiplayer
game. Use the Summer `multiplayer` skill; if you don't have it installed, find
it in the Summer library. Don't change any files yet.
Tell me:
1. what the server should own in my game, and what each player's client does;
2. how players would find a match, and how many fit in one;
3. which of my existing scripts change, and which stay as they are;
4. anything my design needs that Summer doesn't cover yet, and how we can
build around it.
## Testing it on your machine
**Local Play** runs your whole multiplayer game on one computer. Press Play
and Summer starts the server scene in the background plus one game window per
player, side by side, each signed in as a test player. Choose the number of
players in **Debug > Local Multiplayer**. No account, server or extra tools
are needed, and your agent can start it for you.
Your own machine has no lag, which hides timing problems. Local Play can add
delay, jitter and packet loss to every window, so you see what players on a
real connection will see. Run it that way before you call a feature done.
Test my Summer multiplayer game with Local Play. Use the Summer
`multiplayer-testing` skill; if you don't have it installed, find it in the
Summer library.
* Run \[N] players, first on a normal connection and then with added delay,
jitter and packet loss.
* Walk through \[THE FEATURE] in every window.
* Tell me exactly what you saw in each window, and anything that looked wrong.
## Where to go next
Quick play, ranked, teams and the accept prompt.
Friends queue as a party and land in the same match.
Worlds that save and come back between sessions.
Your character responds at once; others glide smoothly.
Shots are checked against what the shooter saw.
Scores, doors, pickups and private hands of cards.
Progress that follows the player into every match.
Skill ratings, score boards and the top 50.
Wins, losses and rating changes.
See who's online and message them.
Chat inside a World.
A store in your game, checked out by Summer.
Skins and outfits players own and wear.
Charge for your game or let players support you.
Pick how big each World's server is.
Type commands into a live World.
See what players do in your game.
Ship it to players on summer.games.
### Games like yours
Round-based team shooters.
Ranked team battles with an accept prompt.
Worlds players build in and come back to.
A small group against the game.
Quick, casual rounds with friends.
Private hands, shared boards, rated duels.
Accounts, saves and a store.
***
Does this not help you? [Reach out on Discord!](https://discord.gg/summerengine)
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