/**** 
* Plugins
****/ 
var tween = LK.import("@upit/tween.v1");

/**** 
* Classes
****/ 
var Bullet = Container.expand(function () {
	var self = Container.call(this);
	var bulletGraphics = self.attachAsset('bullet', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	self.speed = 15;
	self.damage = 5;
	self.update = function () {
		self.y -= self.speed;
	};
	return self;
});
var Mango = Container.expand(function () {
	var self = Container.call(this);
	var mangoGraphics = self.attachAsset('mango', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	self.maxHealth = 100;
	self.health = self.maxHealth;
	self.speed = 2;
	self.coinValue = 1;
	self.lastHealth = self.health;
	self.takeDamage = function (damage) {
		self.health -= damage;
		if (self.health < 0) self.health = 0;
	};
	self.update = function () {
		self.y += self.speed;
		// Flash red when taking damage
		if (self.lastHealth > self.health) {
			LK.effects.flashObject(self, 0xff0000, 300);
		}
		self.lastHealth = self.health;
	};
	return self;
});
var Mustard = Container.expand(function () {
	var self = Container.call(this);
	var mustardGraphics = self.attachAsset('mustard', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	self.maxHealth = 200;
	self.health = self.maxHealth;
	self.speed = 1.5;
	self.coinValue = 2;
	self.lastHealth = self.health;
	self.takeDamage = function (damage) {
		self.health -= damage;
		if (self.health < 0) self.health = 0;
	};
	self.update = function () {
		self.y += self.speed;
		// Flash red when taking damage
		if (self.lastHealth > self.health) {
			LK.effects.flashObject(self, 0xff0000, 300);
		}
		self.lastHealth = self.health;
	};
	return self;
});
var Player = Container.expand(function () {
	var self = Container.call(this);
	var playerGraphics = self.attachAsset('player', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	self.health = 100;
	self.maxHealth = 100;
	return self;
});

/**** 
* Initialize Game
****/ 
var game = new LK.Game({
	backgroundColor: 0x2c3e50
});

/**** 
* Game Code
****/ 
// Game variables
var player;
var bullets = [];
var enemies = [];
var coins = 0;
var playerHealth = 100;
var gameStarted = false;
var enemySpawnTimer = 0;
var enemySpawnRate = 120; // frames between spawns
var difficultyTimer = 0;
var isMouseDown = false;
var mouseX = 0;
var mouseY = 0;
var shootCooldown = 0;
var shootRate = 10; // frames between shots when holding
var currentWave = 1;
var enemiesInWave = 8; // Start with 8 enemies per wave
var enemiesSpawned = 0;
var enemiesKilled = 0;
var waveInProgress = false;
var waveStartDelay = 180; // 3 seconds between waves
var waveDelayTimer = 0;
var upgrade1Cost = 1;
var upgrade2Cost = 3;
var upgrade1Level = 0;
var upgrade2Level = 0;
// Create city background
var cityBuildings = [];
for (var i = 0; i < 12; i++) {
	var buildingType = Math.floor(Math.random() * 3) + 1;
	var building = LK.getAsset('cityBuilding' + buildingType, {
		anchorX: 0.5,
		anchorY: 1
	});
	building.x = i * 180 + 100;
	building.y = 2732;
	building.alpha = 0.3;
	game.addChild(building);
	cityBuildings.push(building);
}
// Create player
player = game.addChild(new Player());
player.x = 2048 / 2;
player.y = 2732 - 150;
// UI Elements
var coinText = new Text2('Coins: 0', {
	size: 60,
	fill: 0xFFFFFF
});
coinText.anchor.set(0, 0);
coinText.x = 150;
coinText.y = 50;
LK.gui.topLeft.addChild(coinText);
var healthText = new Text2('Health: 100', {
	size: 60,
	fill: 0xFF0000
});
healthText.anchor.set(1, 0);
LK.gui.topRight.addChild(healthText);
var waveText = new Text2('Wave: 1', {
	size: 60,
	fill: 0x00FF00
});
waveText.anchor.set(0.5, 0);
LK.gui.top.addChild(waveText);
// Create upgrade buttons
var upgrade1Button = LK.getAsset('upgradeButton', {
	anchorX: 0.5,
	anchorY: 0.5
});
upgrade1Button.x = player.x - 200;
upgrade1Button.y = player.y;
game.addChild(upgrade1Button);
var upgrade2Button = LK.getAsset('upgradeButton', {
	anchorX: 0.5,
	anchorY: 0.5
});
upgrade2Button.x = player.x + 200;
upgrade2Button.y = player.y;
game.addChild(upgrade2Button);
// Add upgrade button labels
var upgrade1Text = new Text2('Upgrade 1\nCost: ' + upgrade1Cost, {
	size: 30,
	fill: 0xFFFFFF
});
upgrade1Text.anchor.set(0.5, 0.5);
upgrade1Text.x = upgrade1Button.x;
upgrade1Text.y = upgrade1Button.y;
game.addChild(upgrade1Text);
var upgrade2Text = new Text2('Upgrade 2\nCost: ' + upgrade2Cost, {
	size: 30,
	fill: 0xFFFFFF
});
upgrade2Text.anchor.set(0.5, 0.5);
upgrade2Text.x = upgrade2Button.x;
upgrade2Text.y = upgrade2Button.y;
game.addChild(upgrade2Text);
// Game functions
function spawnEnemy() {
	var enemy;
	var spawnX = Math.random() * (2048 - 100) + 50;
	// 70% chance for Mango, 30% chance for Mustard
	if (Math.random() < 0.7) {
		enemy = new Mango();
	} else {
		enemy = new Mustard();
	}
	enemy.x = spawnX;
	enemy.y = -50;
	enemy.lastY = enemy.y;
	enemies.push(enemy);
	game.addChild(enemy);
	enemiesSpawned++;
}
function startNewWave() {
	currentWave++;
	enemiesInWave = Math.max(4, enemiesInWave - 1); // Reduce enemies per wave, minimum 4
	enemiesSpawned = 0;
	enemiesKilled = 0;
	waveInProgress = true;
	waveDelayTimer = 0;
	waveText.setText('Wave: ' + currentWave);
	// Make waves progressively harder
	enemySpawnRate = Math.max(30, enemySpawnRate - 5);
}
function fireBullet(targetX, targetY) {
	var bullet = new Bullet();
	bullet.x = player.x;
	bullet.y = player.y - 40;
	bullet.lastY = bullet.y;
	// Calculate angle to target
	var deltaX = targetX - bullet.x;
	var deltaY = targetY - bullet.y;
	var angle = Math.atan2(deltaY, deltaX);
	// Set bullet direction
	bullet.velocityX = Math.cos(angle) * bullet.speed;
	bullet.velocityY = Math.sin(angle) * bullet.speed;
	// Override update to use calculated velocity
	bullet.update = function () {
		bullet.x += bullet.velocityX;
		bullet.y += bullet.velocityY;
	};
	bullets.push(bullet);
	game.addChild(bullet);
	LK.getSound('shoot').play();
}
// Event handlers
game.down = function (x, y, obj) {
	if (gameStarted) {
		// Check if upgrade buttons were clicked
		var localPos = game.toLocal({
			x: x,
			y: y
		});
		// Check upgrade 1 button
		if (Math.abs(localPos.x - upgrade1Button.x) < 60 && Math.abs(localPos.y - upgrade1Button.y) < 40) {
			if (coins >= upgrade1Cost) {
				coins -= upgrade1Cost;
				upgrade1Level++;
				upgrade1Cost *= 2; // Double the cost for next upgrade
				coinText.setText('Coins: ' + coins);
				upgrade1Text.setText('Upgrade 1\nLevel: ' + upgrade1Level + '\nCost: ' + upgrade1Cost);
				// Apply upgrade effect (example: increase damage)
				Bullet.prototype.damage = 5 + upgrade1Level * 2;
			}
			return;
		}
		// Check upgrade 2 button
		if (Math.abs(localPos.x - upgrade2Button.x) < 60 && Math.abs(localPos.y - upgrade2Button.y) < 40) {
			if (coins >= upgrade2Cost) {
				coins -= upgrade2Cost;
				upgrade2Level++;
				upgrade2Cost *= 2; // Double the cost for next upgrade
				coinText.setText('Coins: ' + coins);
				upgrade2Text.setText('Upgrade 2\nLevel: ' + upgrade2Level + '\nCost: ' + upgrade2Cost);
				// Apply upgrade effect (example: increase fire rate)
				shootRate = Math.max(3, 10 - upgrade2Level * 2);
			}
			return;
		}
		isMouseDown = true;
		mouseX = x;
		mouseY = y;
		fireBullet(x, y);
	} else {
		gameStarted = true;
	}
};
game.up = function (x, y, obj) {
	isMouseDown = false;
};
game.move = function (x, y, obj) {
	if (isMouseDown) {
		mouseX = x;
		mouseY = y;
	}
};
// Main game loop
game.update = function () {
	if (!gameStarted) {
		waveInProgress = true; // Start first wave when game begins
		return;
	}
	// Update upgrade button positions
	upgrade1Button.x = player.x - 200;
	upgrade1Button.y = player.y;
	upgrade1Text.x = upgrade1Button.x;
	upgrade1Text.y = upgrade1Button.y;
	upgrade2Button.x = player.x + 200;
	upgrade2Button.y = player.y;
	upgrade2Text.x = upgrade2Button.x;
	upgrade2Text.y = upgrade2Button.y;
	// Handle continuous shooting
	if (isMouseDown) {
		shootCooldown--;
		if (shootCooldown <= 0) {
			fireBullet(mouseX, mouseY);
			shootCooldown = shootRate;
		}
	}
	// Wave management
	if (!waveInProgress) {
		waveDelayTimer++;
		if (waveDelayTimer >= waveStartDelay) {
			startNewWave();
		}
	} else {
		// Spawn enemies for current wave
		enemySpawnTimer++;
		if (enemySpawnTimer >= enemySpawnRate && enemiesSpawned < enemiesInWave) {
			spawnEnemy();
			enemySpawnTimer = 0;
		}
		// Check if wave is complete
		if (enemiesKilled >= enemiesInWave && enemies.length === 0) {
			waveInProgress = false;
			waveDelayTimer = 0;
		}
	}
	// Update bullets
	for (var i = bullets.length - 1; i >= 0; i--) {
		var bullet = bullets[i];
		// Remove bullets that go off screen
		if (bullet.lastY <= 2732 && (bullet.y > 2732 || bullet.y < -50 || bullet.x < -50 || bullet.x > 2098)) {
			bullet.destroy();
			bullets.splice(i, 1);
			continue;
		}
		bullet.lastY = bullet.y;
	}
	// Update enemies and check collisions
	for (var j = enemies.length - 1; j >= 0; j--) {
		var enemy = enemies[j];
		// Remove enemies that reach bottom (player takes damage)
		if (enemy.lastY < 2732 && enemy.y >= 2732) {
			playerHealth -= 20;
			healthText.setText('Health: ' + playerHealth);
			LK.effects.flashScreen(0xff0000, 500);
			if (playerHealth <= 0) {
				LK.setScore(coins);
				LK.showGameOver();
				return;
			}
			enemiesKilled++; // Count as killed for wave progress
			enemy.destroy();
			enemies.splice(j, 1);
			continue;
		}
		// Check bullet collisions
		for (var k = bullets.length - 1; k >= 0; k--) {
			var bullet = bullets[k];
			if (bullet.intersects(enemy)) {
				enemy.takeDamage(bullet.damage);
				LK.getSound('enemyHit').play();
				// Remove bullet
				bullet.destroy();
				bullets.splice(k, 1);
				// Check if enemy is dead
				if (enemy.health <= 0) {
					coins += enemy.coinValue;
					coinText.setText('Coins: ' + coins);
					LK.getSound('enemyDeath').play();
					enemiesKilled++;
					enemy.destroy();
					enemies.splice(j, 1);
				}
				break;
			}
		}
		enemy.lastY = enemy.y;
	}
};

===================================================================
--- original.js
+++ change.js
@@ -111,8 +111,12 @@
 var enemiesKilled = 0;
 var waveInProgress = false;
 var waveStartDelay = 180; // 3 seconds between waves
 var waveDelayTimer = 0;
+var upgrade1Cost = 1;
+var upgrade2Cost = 3;
+var upgrade1Level = 0;
+var upgrade2Level = 0;
 // Create city background
 var cityBuildings = [];
 for (var i = 0; i < 12; i++) {
 	var buildingType = Math.floor(Math.random() * 3) + 1;
@@ -150,8 +154,40 @@
 	fill: 0x00FF00
 });
 waveText.anchor.set(0.5, 0);
 LK.gui.top.addChild(waveText);
+// Create upgrade buttons
+var upgrade1Button = LK.getAsset('upgradeButton', {
+	anchorX: 0.5,
+	anchorY: 0.5
+});
+upgrade1Button.x = player.x - 200;
+upgrade1Button.y = player.y;
+game.addChild(upgrade1Button);
+var upgrade2Button = LK.getAsset('upgradeButton', {
+	anchorX: 0.5,
+	anchorY: 0.5
+});
+upgrade2Button.x = player.x + 200;
+upgrade2Button.y = player.y;
+game.addChild(upgrade2Button);
+// Add upgrade button labels
+var upgrade1Text = new Text2('Upgrade 1\nCost: ' + upgrade1Cost, {
+	size: 30,
+	fill: 0xFFFFFF
+});
+upgrade1Text.anchor.set(0.5, 0.5);
+upgrade1Text.x = upgrade1Button.x;
+upgrade1Text.y = upgrade1Button.y;
+game.addChild(upgrade1Text);
+var upgrade2Text = new Text2('Upgrade 2\nCost: ' + upgrade2Cost, {
+	size: 30,
+	fill: 0xFFFFFF
+});
+upgrade2Text.anchor.set(0.5, 0.5);
+upgrade2Text.x = upgrade2Button.x;
+upgrade2Text.y = upgrade2Button.y;
+game.addChild(upgrade2Text);
 // Game functions
 function spawnEnemy() {
 	var enemy;
 	var spawnX = Math.random() * (2048 - 100) + 50;
@@ -202,8 +238,39 @@
 }
 // Event handlers
 game.down = function (x, y, obj) {
 	if (gameStarted) {
+		// Check if upgrade buttons were clicked
+		var localPos = game.toLocal({
+			x: x,
+			y: y
+		});
+		// Check upgrade 1 button
+		if (Math.abs(localPos.x - upgrade1Button.x) < 60 && Math.abs(localPos.y - upgrade1Button.y) < 40) {
+			if (coins >= upgrade1Cost) {
+				coins -= upgrade1Cost;
+				upgrade1Level++;
+				upgrade1Cost *= 2; // Double the cost for next upgrade
+				coinText.setText('Coins: ' + coins);
+				upgrade1Text.setText('Upgrade 1\nLevel: ' + upgrade1Level + '\nCost: ' + upgrade1Cost);
+				// Apply upgrade effect (example: increase damage)
+				Bullet.prototype.damage = 5 + upgrade1Level * 2;
+			}
+			return;
+		}
+		// Check upgrade 2 button
+		if (Math.abs(localPos.x - upgrade2Button.x) < 60 && Math.abs(localPos.y - upgrade2Button.y) < 40) {
+			if (coins >= upgrade2Cost) {
+				coins -= upgrade2Cost;
+				upgrade2Level++;
+				upgrade2Cost *= 2; // Double the cost for next upgrade
+				coinText.setText('Coins: ' + coins);
+				upgrade2Text.setText('Upgrade 2\nLevel: ' + upgrade2Level + '\nCost: ' + upgrade2Cost);
+				// Apply upgrade effect (example: increase fire rate)
+				shootRate = Math.max(3, 10 - upgrade2Level * 2);
+			}
+			return;
+		}
 		isMouseDown = true;
 		mouseX = x;
 		mouseY = y;
 		fireBullet(x, y);
@@ -225,8 +292,17 @@
 	if (!gameStarted) {
 		waveInProgress = true; // Start first wave when game begins
 		return;
 	}
+	// Update upgrade button positions
+	upgrade1Button.x = player.x - 200;
+	upgrade1Button.y = player.y;
+	upgrade1Text.x = upgrade1Button.x;
+	upgrade1Text.y = upgrade1Button.y;
+	upgrade2Button.x = player.x + 200;
+	upgrade2Button.y = player.y;
+	upgrade2Text.x = upgrade2Button.x;
+	upgrade2Text.y = upgrade2Button.y;
 	// Handle continuous shooting
 	if (isMouseDown) {
 		shootCooldown--;
 		if (shootCooldown <= 0) {