diff --git a/docs/tutorial/01-introduction.md b/docs/tutorial/01-introduction.md
index 70889c64..596099db 100644
--- a/docs/tutorial/01-introduction.md
+++ b/docs/tutorial/01-introduction.md
@@ -1,4 +1,308 @@
----
+---mangodeer-mabar/
+├─ server/
+│  └─ server.js
+├─ public/
+│  ├─ index.html        (lobi + entry)
+│  ├─ lobby.js          (lobby UI & socket)
+│  ├─ game.html         (game canvas page)
+│  ├─ game.js           (phaser client + room support)
+│  ├─ phaser.min.js
+│  └─ assets/
+│     ├─ ... sprites ...
+└─ package.jsonserver.jsindex.htmllobby.jsgame.htmlgame.jsphaser.min.js// server/server.js
+const express = require('express');
+const http = require('http');
+const { Server } = require('socket.io');
+const app = express();
+const server = http.createServer(app);
+const io = new Server(server);
+
+app.use(express.static(__dirname + '/../public'));
+
+// Room model
+// rooms: { roomId: { id, mode, players: [socketId,...], maxPlayers, state: 'waiting'|'playing' } }
+const rooms = {};
+const TICK = 60; // ms
+
+// Simple players store (authoritative state)
+const players = {}; // { socketId: { x,y,vx,vy,facing,hp,roomId,anim } }
+
+function createRoom(mode) {
+  const id = 'room-' + Math.random().toString(36).slice(2,9);
+  const maxPlayers = mode === '1v1' ? 2 : 4;
+  rooms[id] = { id, mode, players: [], maxPlayers, state: 'waiting' };
+  return rooms[id];
+}
+
+io.on('connection', socket => {
+  console.log('conn', socket.id);
+  // send current rooms list
+  socket.emit('lobby:rooms', Object.values(rooms).map(r => ({
+    id: r.id, mode: r.mode, players: r.players.length, maxPlayers: r.maxPlayers, state: r.state
+  })));
+
+  // Create room
+  socket.on('lobby:create', (mode, cb) => {
+    if (!['1v1','2v2'].includes(mode)) return cb && cb({ ok:false, err:'bad-mode' });
+    const room = createRoom(mode);
+    console.log('room created', room.id, mode);
+    io.emit('lobby:rooms', Object.values(rooms).map(r => ({
+      id: r.id, mode: r.mode, players: r.players.length, maxPlayers: r.maxPlayers, state: r.state
+    })));
+    cb && cb({ ok:true, roomId: room.id });
+  });
+
+  // Join room
+  socket.on('lobby:join', (roomId, cb) => {
+    const room = rooms[roomId];
+    if (!room) return cb && cb({ ok:false, err:'no-room' });
+    if (room.players.length >= room.maxPlayers) return cb && cb({ ok:false, err:'full' });
+
+    // add to room
+    room.players.push(socket.id);
+    socket.join(roomId);
+    players[socket.id] = {
+      x: 200 + Math.random()*200,
+      y: 300,
+      vx: 0, vy: 0,
+      facing: 'right',
+      hp: 100,
+      anim: 'idle',
+      roomId
+    };
+    console.log(`${socket.id} joined ${roomId}`);
+
+    // notify room members
+    io.to(roomId).emit('room:update', {
+      id: room.id, players: room.players.slice(), maxPlayers: room.maxPlayers, mode: room.mode, state: room.state
+    });
+    io.emit('lobby:rooms', Object.values(rooms).map(r => ({
+      id: r.id, mode: r.mode, players: r.players.length, maxPlayers: r.maxPlayers, state: r.state
+    })));
+
+    // auto-start when full
+    if (room.players.length === room.maxPlayers) {
+      room.state = 'playing';
+      // announce start
+      io.to(roomId).emit('room:start', { roomId: room.id, serverTick: Date.now() });
+      console.log('room started', roomId);
+    }
+
+    cb && cb({ ok:true, roomId: room.id });
+  });
+
+  // Leave room
+  socket.on('lobby:leave', (roomId, cb) => {
+    const room = rooms[roomId];
+    if (!room) return cb && cb({ ok:false, err:'no-room' });
+    const idx = room.players.indexOf(socket.id);
+    if (idx !== -1) room.players.splice(idx,1);
+    socket.leave(roomId);
+    if (players[socket.id]) delete players[socket.id];
+    // if empty, delete room
+    if (room.players.length === 0) {
+      delete rooms[roomId];
+    } else {
+      room.state = 'waiting';
+      io.to(roomId).emit('room:update', {
+        id: room.id, players: room.players.slice(), maxPlayers: room.maxPlayers, mode: room.mode, state: room.state
+      });
+    }
+    io.emit('lobby:rooms', Object.values(rooms).map(r => ({
+      id: r.id, mode: r.mode, players: r.players.length, maxPlayers: r.maxPlayers, state: r.state
+    })));
+    cb && cb({ ok:true });
+  });
+
+  // client input (per-room) — minimal
+  socket.on('input', data => {
+    const p = players[socket.id];
+    if (!p) return;
+    // store last input on server-side for tick processing
+    p.pendingInput = data; // { left, right, up, attack, timestamp }
+  });
+
+  socket.on('disconnect', () => {
+    console.log('disc', socket.id);
+    const p = players[socket.id];
+    if (p && p.roomId) {
+      const room = rooms[p.roomId];
+      if (room) {
+        const idx = room.players.indexOf(socket.id);
+        if (idx !== -1) room.players.splice(idx,1);
+        io.to(room.id).emit('room:update', {
+          id: room.id, players: room.players.slice(), maxPlayers: room.maxPlayers, mode: room.mode, state: room.state
+        });
+        if (room.players.length === 0) delete rooms[room.id];
+        else room.state = 'waiting';
+      }
+    }
+    delete players[socket.id];
+    io.emit('lobby:rooms', Object.values(rooms).map(r => ({
+      id: r.id, mode: r.mode, players: r.players.length, maxPlayers: r.maxPlayers, state: r.state
+    })));
+  });
+});
+
+// physics & state tick per-room
+setInterval(() => {
+  // iterate rooms in playing state
+  for (const roomId in rooms) {
+    const room = rooms[roomId];
+    if (room.state !== 'playing') continue;
+
+    // step players that are in that room
+    const dt = TICK/1000;
+    // apply inputs
+    for (const sid of room.players) {
+      const p = players[sid];
+      if (!p) continue;
+      const inData = p.pendingInput || {};
+      // movement
+      const speed = 200;
+      p.vx = (inData.left ? -speed : 0) + (inData.right ? speed : 0);
+      if (p.vx < 0) p.facing = 'left'; else if (p.vx > 0) p.facing = 'right';
+      // jump
+      if (inData.up && Math.abs(p.vy) < 0.1) p.vy = -380;
+      // simple attack handling
+      if (inData.attack) {
+        // mark as attack to show on client
+        p.anim = 'attack';
+        for (const sid2 of room.players) {
+          if (sid2 === sid) continue;
+          const q = players[ssocket.id2r.stater.id200room.idroom.stateio.top.pendingInputnowp.facingp.vxp.animp.vyq.hp7012000<!doctype html>
+<html>
+<head>
+  <meta charset="utf-8" />
+  <title>MangoDeer Mabar — Lobby</title>
+  <style>
+    body{font-family:Arial,Helvetica,sans-serif;margin:20px;}
+    #rooms { margin-top: 12px; }
+    .room { padding:8px;border:1px solid #ddd;margin-bottom:6px;display:flex;justify-content:space-between;align-items:center;}
+    button { margin-left:8px;}
+  </style>
+</head>
+<body>
+  <h2>Mangodeer Mabar — Lobi</h2>
+  <div>
+    Buat bilik:
+    <button id="create1v1">Create 1v1</button>
+    <button id="create2v2">Create 2v2</button>
+  </div>
+
+  <div id="rooms"><em>Loading rooms...</em></div>
+
+  <script src="/socket.io/socket.io.js"></script>
+  <script src="lobby.js"></script>
+</body>
+</html>process.env.PORTsocket.io/socket.io.jsconst socket = io();
+const roomsDiv = document.getElementById('rooms');
+
+function renderRooms(list) {
+  if (!list || list.length === 0) {
+    roomsDiv.innerHTML = '<em>No rooms yet.</em>';
+    return;
+  }
+  roomsDiv.innerHTML = '';
+  list.forEach(r => {
+    const div = document.createElement('div');
+    div.className = 'room';
+    div.innerHTML = `<div>
+      <strong>${r.id}</strong> — ${r.mode} — ${r.players}/${r.maxPlayers} — ${r.state}
+    </div>`;
+    const controls = document.createElement('div');
+    const joinBtn = document.createElement('button');
+    joinBtn.textContent = 'Join';
+    joinBtn.disabled = r.players >= r.maxPlayers || r.state !== 'waiting';
+    joinBtn.onclick = () => {
+      socket.emit('lobby:join', r.id, (res) => {
+        if (res && res.ok) {
+          // open game page with room param
+          location.href = `game.html?room=${r.id}`;
+        } else {
+          alert('Gagal join: ' + (res.err||''));
+        }
+      });
+    };
+    controls.appendChild(joinBtn);
+    div.appendChild(controls);
+    roomsDiv.appendChild(div);
+  });
+}
+
+socket.on('lobby:rooms', (list) => {
+  renderRooms(list);
+});
+
+document.getElementById('create1v1').onclick = () => {
+  socket.emit('lobby:create', '1v1', (res) => {
+    if (res.ok) {
+      location.href = `game.html?room=${res.roomId}`;
+    } else alert('Gagal create: '+(res.err||''));
+  });
+};
+document.getElementById('create2v2').onclick = () => {
+  socket.emit('lobby:create', '2v2', (res) => {
+    if (res.ok) location.href = `game.html?room=${res.roomId}`;
+    else alert('Gagal create: '+(res.err||''));
+  });
+};list.lengthdiv.classNameroomsDiv.innerHTMLdiv.innerHTMLjoinBtn.textContentjoinBtn.disabledr.playersr.maxPlayersjoinBtn.onclicklocation.href<!doctype html>
+<html>
+<head><meta charset="utf-8"/><title>Game</title></head>
+<body style="margin:0;">
+  <div id="ui" style="position:fixed;left:10px;top:10px;z-index:50;background:rgba(255,255,255,0.8);padding:6px;border-radius:6px;">
+    <button id="leave">Leave Room</button>
+    <span id="roomInfo"></span>
+  </div>
+
+  <script src="phaser.min.js"></script>
+  <script src="/socket.io/socket.io.js"></script>
+  <script src="game.js"></script>
+</body>
+</html>id2];
+          if (!q) continue;
+          const dx = Math.abs(q.x - p.x);
+          const dy = Math.abs(q.y - p.y);
+          if (dx < 70 && dy < 50) {
+            q.hp -= 30;
+            if (q.hp < 0) q.hp = 0;
+          }
+        }
+      } else {
+        p.anim = Math.abs(p.vx) > 0 ? 'run' : 'idle';
+      }
+    }
+
+    // integrate motion & gravity & ground
+    for (const sid of room.players) {
+      const p = players[sid];
+      if (!p) continue;
+      p.x += p.vx * dt;
+      p.y += p.vy * dt;
+      p.vy += 1200 * dt; // gravity
+      if (p.y > 300) { p.y = 300; p.vy = 0; }
+      // bounds
+      if (p.x < 0) p.x = 0;
+      if (p.x > 760) p.x = 760;
+    }
+
+    // broadcast state snapshot for this room only
+    const snapshot = {};
+    for (const sid of room.players) {
+      snapshot[sid] = {
+        x: Math.round(players[sid].x),
+        y: Math.round(players[sid].y),
+        facing: players[sid].facing,
+        hp: players[sid].hp,
+        anim: players[sid].anim
+      };
+    }
+    io.to(roomId).emit('state:sync', snapshot);
+  }
+}, TICK);
+
+const PORT = process.env.PORT || 3000;
+server.listen(PORT, () => console.log('Server running on', PORT));
 title: Tutorial - Introduction
 sidebar_label: Introduction
 slug: introduction