===================================================================
--- original.js
+++ change.js
@@ -1,6 +1,453 @@
-/****
+/**** 
+* Plugins
+****/ 
+var tween = LK.import("@upit/tween.v1");
+
+/**** 
+* Classes
+****/ 
+// Bullet fired by soldiers
+var Bullet = Container.expand(function () {
+	var self = Container.call(this);
+	var bulletAsset = self.attachAsset('bullet', {
+		anchorX: 0.5,
+		anchorY: 0.5
+	});
+	self.speed = 32;
+	self.target = null; // Zombie instance
+	self.damage = 1;
+	self.update = function () {
+		if (!self.target || self.target.isDead) {
+			self.destroy();
+			return;
+		}
+		// Move towards target
+		var dx = self.target.x - self.x;
+		var dy = self.target.y - self.y;
+		var dist = Math.sqrt(dx * dx + dy * dy);
+		if (dist < 32) {
+			// Hit!
+			self.target.takeDamage(self.damage);
+			self.destroy();
+			return;
+		}
+		var step = self.speed;
+		self.x += dx / dist * step;
+		self.y += dy / dist * step;
+	};
+	return self;
+});
+// Gold coin dropped by zombies
+var Gold = Container.expand(function () {
+	var self = Container.call(this);
+	var goldAsset = self.attachAsset('gold', {
+		anchorX: 0.5,
+		anchorY: 0.5
+	});
+	self.value = 1;
+	self.life = 180; // 3 seconds
+	self.update = function () {
+		self.life--;
+		if (self.life <= 0) {
+			self.destroy();
+		}
+	};
+	return self;
+});
+// Soldier on a watchtower
+var Soldier = Container.expand(function () {
+	var self = Container.call(this);
+	var soldierAsset = self.attachAsset('soldier', {
+		anchorX: 0.5,
+		anchorY: 0.5
+	});
+	self.level = 1;
+	self.fireRate = 60; // frames between shots
+	self.fireTimer = 0;
+	self.range = 600;
+	self.upgradeCost = 5;
+	self.parentTower = null;
+	self.update = function () {
+		if (!self.parentTower) return;
+		self.fireTimer--;
+		if (self.fireTimer <= 0) {
+			// Find nearest zombie in range
+			var nearest = null;
+			var minDist = self.range;
+			for (var i = 0; i < zombies.length; i++) {
+				var z = zombies[i];
+				if (z.isDead) continue;
+				var dx = z.x - self.x;
+				var dy = z.y - self.y;
+				var dist = Math.sqrt(dx * dx + dy * dy);
+				if (dist < minDist) {
+					minDist = dist;
+					nearest = z;
+				}
+			}
+			if (nearest) {
+				// Fire!
+				var bullet = new Bullet();
+				bullet.x = self.x;
+				bullet.y = self.y;
+				bullet.target = nearest;
+				bullet.damage = self.level;
+				bullets.push(bullet);
+				game.addChild(bullet);
+				LK.getSound('shoot').play();
+				self.fireTimer = Math.max(20, self.fireRate - self.level * 8);
+			}
+		}
+	};
+	self.upgrade = function () {
+		self.level++;
+		self.fireRate = Math.max(20, self.fireRate - 8);
+		self.upgradeCost += 5;
+		// Animate upgrade
+		tween(self, {
+			scaleX: 1.2,
+			scaleY: 1.2
+		}, {
+			duration: 120,
+			onFinish: function onFinish() {
+				tween(self, {
+					scaleX: 1,
+					scaleY: 1
+				}, {
+					duration: 120
+				});
+			}
+		});
+	};
+	return self;
+});
+// Watchtower (can have a soldier)
+var Watchtower = Container.expand(function () {
+	var self = Container.call(this);
+	var towerAsset = self.attachAsset('watchtower', {
+		anchorX: 0.5,
+		anchorY: 1
+	});
+	self.soldier = null;
+	self.index = 0;
+	// For tap detection
+	self.down = function (x, y, obj) {
+		if (!self.soldier) {
+			// Recruit soldier
+			if (game.gold >= 5) {
+				game.gold -= 5;
+				var s = new Soldier();
+				s.x = self.x;
+				s.y = self.y - 80;
+				s.parentTower = self;
+				self.soldier = s;
+				soldiers.push(s);
+				game.addChild(s);
+				updateGoldText();
+				// Animate
+				tween(s, {
+					alpha: 0
+				}, {
+					duration: 0,
+					onFinish: function onFinish() {
+						tween(s, {
+							alpha: 1
+						}, {
+							duration: 200
+						});
+					}
+				});
+			}
+		} else {
+			// Upgrade soldier
+			if (game.gold >= self.soldier.upgradeCost) {
+				game.gold -= self.soldier.upgradeCost;
+				self.soldier.upgrade();
+				updateGoldText();
+			}
+		}
+	};
+	return self;
+});
+// Zombie enemy
+var Zombie = Container.expand(function () {
+	var self = Container.call(this);
+	var zombieAsset = self.attachAsset('zombie', {
+		anchorX: 0.5,
+		anchorY: 0.5
+	});
+	self.maxHp = 2;
+	self.hp = self.maxHp;
+	self.speed = 2 + Math.random() * 1.5;
+	self.isDead = false;
+	self.targetX = 0;
+	self.targetY = 0;
+	self.takeDamage = function (dmg) {
+		if (self.isDead) return;
+		self.hp -= dmg;
+		if (self.hp <= 0) {
+			self.die();
+		} else {
+			// Flash red
+			tween(self, {
+				tint: 0xFF0000
+			}, {
+				duration: 80,
+				onFinish: function onFinish() {
+					tween(self, {
+						tint: 0x4CAF50
+					}, {
+						duration: 120
+					});
+				}
+			});
+		}
+	};
+	self.die = function () {
+		if (self.isDead) return;
+		self.isDead = true;
+		LK.getSound('zombieDie').play();
+		// Drop gold
+		var gold = new Gold();
+		gold.x = self.x;
+		gold.y = self.y;
+		golds.push(gold);
+		game.addChild(gold);
+		// Animate fade out
+		tween(self, {
+			alpha: 0
+		}, {
+			duration: 200,
+			onFinish: function onFinish() {
+				self.destroy();
+			}
+		});
+	};
+	self.update = function () {
+		if (self.isDead) return;
+		var dx = self.targetX - self.x;
+		var dy = self.targetY - self.y;
+		var dist = Math.sqrt(dx * dx + dy * dy);
+		if (dist < 30) {
+			// Reached gate
+			self.isDead = true;
+			self.destroy();
+			// Damage gate
+			game.gateHp--;
+			LK.effects.flashObject(game.castleGate, 0xFF0000, 400);
+			if (game.gateHp <= 0) {
+				LK.effects.flashScreen(0xFF0000, 1000);
+				LK.showGameOver();
+			}
+			return;
+		}
+		var step = self.speed;
+		self.x += dx / dist * step;
+		self.y += dy / dist * step;
+	};
+	return self;
+});
+
+/**** 
 * Initialize Game
-****/
+****/ 
 var game = new LK.Game({
-	backgroundColor: 0x000000
-});
\ No newline at end of file
+	backgroundColor: 0x222233
+});
+
+/**** 
+* Game Code
+****/ 
+// Music
+// Sound for zombie death
+// Sound for collecting gold
+// Sound for shooting
+// Gold coin
+// Bullet
+// Zombie
+// Soldier
+// Watchtower base
+// Castle gate (center bottom)
+// Play music
+LK.playMusic('castleTheme');
+// Game variables
+var zombies = [];
+var bullets = [];
+var golds = [];
+var soldiers = [];
+var towers = [];
+game.gateHp = 5;
+game.gold = 10;
+game.wave = 1;
+game.waveTimer = 0;
+// Castle gate
+game.castleGate = LK.getAsset('castleGate', {
+	anchorX: 0.5,
+	anchorY: 1,
+	x: 1024,
+	y: 2732 - 40
+});
+game.addChild(game.castleGate);
+// Watchtower positions (left, center, right, top-left, top-right)
+var towerPositions = [{
+	x: 400,
+	y: 1800
+}, {
+	x: 1024,
+	y: 1700
+}, {
+	x: 1648,
+	y: 1800
+}, {
+	x: 700,
+	y: 1200
+}, {
+	x: 1348,
+	y: 1200
+}];
+for (var i = 0; i < towerPositions.length; i++) {
+	var pos = towerPositions[i];
+	var tower = new Watchtower();
+	tower.x = pos.x;
+	tower.y = pos.y;
+	tower.index = i;
+	towers.push(tower);
+	game.addChild(tower);
+}
+// GUI: Gold display
+var goldTxt = new Text2('Gold: 10', {
+	size: 90,
+	fill: 0xFFD700
+});
+goldTxt.anchor.set(0.5, 0);
+LK.gui.top.addChild(goldTxt);
+// GUI: Gate HP display
+var hpTxt = new Text2('Gate: 5', {
+	size: 90,
+	fill: 0xFFFFFF
+});
+hpTxt.anchor.set(0.5, 0);
+LK.gui.topRight.addChild(hpTxt);
+// GUI: Wave display
+var waveTxt = new Text2('Wave: 1', {
+	size: 80,
+	fill: 0x00BFFF
+});
+waveTxt.anchor.set(0.5, 0);
+LK.gui.bottom.addChild(waveTxt);
+function updateGoldText() {
+	goldTxt.setText('Gold: ' + game.gold);
+}
+function updateHpText() {
+	hpTxt.setText('Gate: ' + game.gateHp);
+}
+function updateWaveText() {
+	waveTxt.setText('Wave: ' + game.wave);
+}
+// Handle collecting gold
+game.down = function (x, y, obj) {
+	// Check if gold was tapped
+	for (var i = golds.length - 1; i >= 0; i--) {
+		var g = golds[i];
+		var dx = g.x - x;
+		var dy = g.y - y;
+		if (dx * dx + dy * dy < 900) {
+			// Collect
+			LK.getSound('coin').play();
+			game.gold += g.value;
+			updateGoldText();
+			g.destroy();
+			golds.splice(i, 1);
+			return;
+		}
+	}
+	// Check if a tower was tapped
+	for (var j = 0; j < towers.length; j++) {
+		var t = towers[j];
+		var tx = t.x,
+			ty = t.y;
+		if (x > tx - 60 && x < tx + 60 && y > ty - 220 && y < ty) {
+			t.down(x, y, obj);
+			return;
+		}
+	}
+};
+// Main update loop
+game.update = function () {
+	// Update gate HP and gold
+	updateHpText();
+	// Update all zombies
+	for (var i = zombies.length - 1; i >= 0; i--) {
+		var z = zombies[i];
+		z.update();
+		if (z.isDead && z.alpha === 0) {
+			z.destroy();
+			zombies.splice(i, 1);
+		}
+	}
+	// Update all bullets
+	for (var i = bullets.length - 1; i >= 0; i--) {
+		var b = bullets[i];
+		b.update();
+		if (b.destroyed) {
+			bullets.splice(i, 1);
+		}
+	}
+	// Update all golds
+	for (var i = golds.length - 1; i >= 0; i--) {
+		var g = golds[i];
+		g.update();
+		if (g.life <= 0 || g.destroyed) {
+			g.destroy();
+			golds.splice(i, 1);
+		}
+	}
+	// Update all soldiers
+	for (var i = 0; i < soldiers.length; i++) {
+		soldiers[i].update();
+	}
+	// Spawn new wave every 180 ticks (3 seconds)
+	game.waveTimer++;
+	if (game.waveTimer >= 180) {
+		game.waveTimer = 0;
+		spawnWave();
+	}
+};
+function spawnWave() {
+	var n = 2 + Math.floor(game.wave * 0.7);
+	for (var i = 0; i < n; i++) {
+		var z = new Zombie();
+		// Spawn from random edge
+		var edge = Math.floor(Math.random() * 4);
+		var zx, zy;
+		if (edge === 0) {
+			// left
+			zx = -60;
+			zy = 1000 + Math.random() * 1200;
+		} else if (edge === 1) {
+			// right
+			zx = 2048 + 60;
+			zy = 1000 + Math.random() * 1200;
+		} else if (edge === 2) {
+			// top
+			zx = 400 + Math.random() * 1200;
+			zy = -80;
+		} else {
+			// bottom (rare)
+			zx = 400 + Math.random() * 1200;
+			zy = 2732 + 80;
+		}
+		z.x = zx;
+		z.y = zy;
+		z.targetX = 1024;
+		z.targetY = 2732 - 100;
+		// Increase HP and speed with wave
+		z.maxHp = 2 + Math.floor(game.wave / 2);
+		z.hp = z.maxHp;
+		z.speed = 2 + Math.random() * 1.5 + game.wave * 0.15;
+		zombies.push(z);
+		game.addChild(z);
+	}
+	game.wave++;
+	updateWaveText();
+}
\ No newline at end of file