/**** 
* Classes
****/ 
// Bullet class for player
var Bullet = Container.expand(function () {
	var self = Container.call(this);
	self.assetId = 'playerBullet';
	var bulletGraphics = self.attachAsset(self.assetId, {
		anchorX: 0.5,
		anchorY: 0.5
	});
	// Bullet speed
	self.speed = -15;
	// Bullet update method
	self.update = function () {
		self.y += self.speed;
	};
});
// Enemy class
var Enemy = Container.expand(function () {
	var self = Container.call(this);
	var enemyGraphics = self.attachAsset('enemyShip', {
		anchorX: 0.5,
		anchorY: 0.5,
		width: 200,
		height: 200
	});
	// Enemy update method
	self.update = function () {
		// Enemies will slowly descend
		self.y += 0.5;
		// If enemy reaches the bottom of the screen
		if (self.y >= 2732) {
			// Destroy the enemy
			self.destroy();
		}
	};
});
// New enemy class
var EnemyPan = Container.expand(function () {
	var self = Container.call(this);
	var enemyGraphics = self.attachAsset('enemyPan', {
		anchorX: 0.5,
		anchorY: 0.5,
		width: 200,
		height: 200
	});
	// Enemy update method
	self.update = function () {
		// Enemies will slowly descend
		self.y += 0.5;
		// If enemy reaches the bottom of the screen
		if (self.y >= 2732) {
			// Destroy the enemy
			self.destroy();
		}
	};
});
// Assets are automatically created and managed by the LK engine based on usage in the game code.
// Player spaceship class
var Player = Container.expand(function () {
	var self = Container.call(this);
	var playerGraphics = self.attachAsset('playerShip', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	// Player movement speed
	self.speed = 10;
	// Update method for player movement
	self.update = function () {
		if (this.moveLeft) {
			this.x -= this.speed;
		}
		if (this.moveRight) {
			this.x += this.speed;
		}
	};
	// Ensure player stays within game bounds
	self.limitBounds = function () {
		this.x = Math.max(this.x, 0);
		this.x = Math.min(this.x, 2048);
	};
});
// PowerUp class
var PowerUp = Container.expand(function () {
	var self = Container.call(this);
	var powerUpGraphics = self.attachAsset('powerUp', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	// PowerUp update method
	self.update = function () {
		// PowerUps will slowly descend
		self.y += 0.5;
		// If PowerUp reaches the bottom of the screen
		if (self.y >= 2732) {
			self.destroy();
		}
	};
});

/**** 
* Initialize Game
****/ 
var game = new LK.Game({
	backgroundColor: 0x000000 // Initialize game with black background
});

/**** 
* Game Code
****/ 
// Initialize background
var background = game.addChild(LK.getAsset('background', {
	anchorX: 0.0,
	anchorY: 0.0,
	x: 0,
	y: 0,
	width: 2048,
	height: 2732
}));
// Initialize player
var player = game.addChild(new Player());
player.x = 1024; // Start in the middle of the game width
player.y = 2500; // Start near the bottom of the game height
// Initialize enemies
var enemies = [];
for (var i = 0; i < 5; i++) {
	for (var j = 0; j < 10; j++) {
		var enemy;
		// Replace one enemy with a power up
		if (i == 2 && j == 5) {
			enemy = new PowerUp();
		} else {
			// Add the new enemy type to every second row
			if (i % 2 == 0) {
				enemy = new EnemyPan();
			} else {
				enemy = new Enemy();
			}
		}
		enemy.x = 100 + j * 325; // Increase horizontal spacing between enemies
		enemy.y = 100 + i * 325; // Increase vertical spacing between enemies
		game.addChild(enemy);
		enemies.push(enemy);
	}
}
// Initialize bullets array
var bullets = [];
// Touch controls for player movement
game.down = function (x, y, obj) {
	if (x < 1024) {
		player.moveLeft = true;
		player.moveRight = false;
	} else {
		player.moveRight = true;
		player.moveLeft = false;
	}
};
game.up = function (x, y, obj) {
	player.moveLeft = false;
	player.moveRight = false;
};
// Fire bullet on touch
game.move = function (x, y, obj) {
	var bullet = new Bullet();
	bullet.x = player.x;
	bullet.y = player.y - 50; // Start bullet at the top of the player
	game.addChild(bullet);
	bullets.push(bullet);
};
// Game update function
game.update = function () {
	// Update player position and keep within bounds
	player.update();
	player.limitBounds();
	// Update all bullets
	for (var i = bullets.length - 1; i >= 0; i--) {
		bullets[i].update();
		// Remove bullets that go off screen
		if (bullets[i].y < 0) {
			bullets[i].destroy();
			bullets.splice(i, 1);
		}
	}
	// Update all enemies
	for (var i = 0; i < enemies.length; i++) {
		enemies[i].update();
	}
	// Collision detection between bullets and enemies
	for (var i = bullets.length - 1; i >= 0; i--) {
		for (var j = enemies.length - 1; j >= 0; j--) {
			if (bullets[i].intersects(enemies[j])) {
				bullets[i].destroy();
				bullets.splice(i, 1);
				if (!(enemies[j] instanceof PowerUp)) {
					enemies[j].destroy();
					enemies.splice(j, 1);
				}
				break; // Exit the inner loop if a collision is detected
			}
		}
	}
	// Collision detection between player and enemies
	for (var j = 0; j < enemies.length; j++) {
		if (player.intersects(enemies[j])) {
			if (enemies[j] instanceof PowerUp) {
				// Handle power up
				enemies[j].destroy();
				enemies.splice(j, 1);
				// Change the player's bullet asset to the power up's asset
				Bullet.prototype.assetId = 'powerUp';
			} else {
				// Flash screen red for 1 second (1000ms) to show we are dead.
				LK.effects.flashScreen(0xff0000, 1000);
				// Show game over. The game will be automatically paused while game over is showing.
				LK.showGameOver(); // Calling this will destroy the 'Game' and reset entire game state.
				break; // Exit the loop if a collision is detected
			}
		}
	}
};

===================================================================
--- original.js
+++ change.js
@@ -3,9 +3,10 @@
 ****/ 
 // Bullet class for player
 var Bullet = Container.expand(function () {
 	var self = Container.call(this);
-	var bulletGraphics = self.attachAsset('playerBullet', {
+	self.assetId = 'playerBullet';
+	var bulletGraphics = self.attachAsset(self.assetId, {
 		anchorX: 0.5,
 		anchorY: 0.5
 	});
 	// Bullet speed
@@ -205,9 +206,10 @@
 			if (enemies[j] instanceof PowerUp) {
 				// Handle power up
 				enemies[j].destroy();
 				enemies.splice(j, 1);
-				// Add power up effect here
+				// Change the player's bullet asset to the power up's asset
+				Bullet.prototype.assetId = 'powerUp';
 			} else {
 				// Flash screen red for 1 second (1000ms) to show we are dead.
 				LK.effects.flashScreen(0xff0000, 1000);
 				// Show game over. The game will be automatically paused while game over is showing.