/**** 
* Classes
****/ 
// Bullet class
var Bullet = Container.expand(function () {
	var self = Container.call(this);
	var bulletGraphics = self.attachAsset('bullet', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	self.speed = -10;
	self.move = function () {
		self.y += self.speed;
	};
});
// Assets will be automatically created based on usage in the code.
// Player class
var Player = Container.expand(function () {
	var self = Container.call(this);
	var playerGraphics = self.attachAsset('player', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	self.speed = 5;
	self.move = function (direction) {
		if (direction === 'left' && self.x > 0) {
			self.x -= self.speed;
		} else if (direction === 'right' && self.x < 2048) {
			self.x += self.speed;
		}
	};
});
// Zombie class
var Zombie = Container.expand(function () {
	var self = Container.call(this);
	var zombieGraphics = self.attachAsset('zombie', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	self.speed = 2;
	self.move = function () {
		self.y += self.speed;
	};
});

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

/**** 
* Game Code
****/ 
var sky = game.addChild(LK.getAsset('sky', {
	anchorX: 0.5,
	anchorY: 0.5,
	x: 1024,
	y: 1366
}));
var background = game.addChild(LK.getAsset('background', {
	anchorX: 0.5,
	anchorY: 0.5,
	x: 1024,
	y: 1366
}));
var player = game.addChild(new Player('player'));
player.x = 1024; // Center horizontally
player.y = 2500; // Near bottom
var zombies = [];
var bullets = [];
var score = 0;
var combo = 0;
var scoreTxt = new Text2(score.toString(), {
	size: 150,
	fill: "#ffffff"
});
LK.gui.top.addChild(scoreTxt);
// Create zombies at intervals
var zombieInterval = LK.setInterval(function () {
	var zombie = new Zombie();
	zombie.x = Math.random() * 2048; // Random horizontal position
	zombie.y = 0; // Start from top
	zombies.push(zombie);
	game.addChild(zombie);
}, 2000);
// Touch event to move player and shoot bullets
game.on('move', function (obj) {
	var pos = obj.event.getLocalPosition(game);
	if (pos.x < player.x) {
		player.move('left');
	} else if (pos.x > player.x) {
		player.move('right');
	}
});
game.on('down', function (obj) {
	var bullet = new Bullet();
	bullet.x = player.x;
	bullet.y = player.y;
	bullets.push(bullet);
	game.addChild(bullet);
});
// Game tick
LK.on('tick', function () {
	// Move zombies
	for (var i = zombies.length - 1; i >= 0; i--) {
		zombies[i].move();
		if (zombies[i].y > 2732) {
			// Off screen
			zombies[i].destroy();
			zombies.splice(i, 1);
		}
	}
	// Move bullets
	for (var j = bullets.length - 1; j >= 0; j--) {
		bullets[j].move();
		if (bullets[j].y < 0) {
			// Off screen
			bullets[j].destroy();
			bullets.splice(j, 1);
			combo = 0; // Reset combo multiplier when a bullet misses
		}
	}
	// Check for bullet-zombie collisions
	for (var b = bullets.length - 1; b >= 0; b--) {
		for (var z = zombies.length - 1; z >= 0; z--) {
			if (bullets[b] && zombies[z] && bullets[b].intersects(zombies[z])) {
				bullets[b].destroy();
				bullets.splice(b, 1);
				zombies[z].destroy();
				zombies.splice(z, 1);
				combo += 1; // Increase combo multiplier on zombie kill
				score += combo; // Increase score by combo multiplier
				LK.setScore(score);
				scoreTxt.setText(score.toString());
				if (score === 10) {
					player.destroy();
					player = game.addChild(new Player('playerType2'));
					player.x = 1024; // Center horizontally
					player.y = 2500; // Near bottom
				} else if (score === 20) {
					player.destroy();
					player = game.addChild(new Player('playerType3'));
					player.x = 1024; // Center horizontally
					player.y = 2500; // Near bottom
				}
				break;
			}
		}
	}
});

===================================================================
--- original.js
+++ change.js
@@ -52,8 +52,14 @@
 
 /**** 
 * Game Code
 ****/ 
+var sky = game.addChild(LK.getAsset('sky', {
+	anchorX: 0.5,
+	anchorY: 0.5,
+	x: 1024,
+	y: 1366
+}));
 var background = game.addChild(LK.getAsset('background', {
 	anchorX: 0.5,
 	anchorY: 0.5,
 	x: 1024,