/**** 
* Classes
****/ 
//<Assets used in the game will automatically appear here>
// Define the Missile class
var Missile = Container.expand(function () {
	var self = Container.call(this);
	var missileGraphics = self.attachAsset('missile', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	self.speed = 5;
	self.update = function () {
		self.y += self.speed;
		if (self.y > 2732) {
			self.destroy();
		}
	};
});
// Define the Player class
var Player = Container.expand(function () {
	var self = Container.call(this);
	var playerGraphics = self.attachAsset('player', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	self.down = function (x, y, obj) {
		self.x = x;
		self.y = y;
	};
});

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

/**** 
* Game Code
****/ 
// Attach the background image to the game
var background = game.attachAsset('background', {
	anchorX: 0.5,
	anchorY: 0.5
});
background.x = 2048 / 2;
background.y = 2732 / 2;
// Initialize player
var player = game.addChild(new Player());
player.x = 2048 / 2;
player.y = 2732 - 200;
// Initialize missiles array
var missiles = [];
// Handle player movement
game.down = function (x, y, obj) {
	player.x = x;
	player.y = y;
};
// Update game state
game.update = function () {
	// Spawn missiles
	if (LK.ticks % 60 == 0) {
		var newMissile = new Missile();
		newMissile.x = Math.random() * 2048;
		newMissile.y = -50;
		missiles.push(newMissile);
		game.addChild(newMissile);
	}
	// Update missiles
	for (var i = missiles.length - 1; i >= 0; i--) {
		if (missiles[i].intersects(player)) {
			LK.effects.flashScreen(0xff0000, 1000);
			LK.showGameOver();
		}
		if (missiles[i].y > 2732) {
			missiles[i].destroy();
			missiles.splice(i, 1);
		}
	}
};

===================================================================
--- original.js
+++ change.js
@@ -39,16 +39,15 @@
 
 /**** 
 * Game Code
 ****/ 
-// Add a background image
-// Initialize background
-var background = game.addChild(LK.getAsset('background', {
-	anchorX: 0.0,
-	anchorY: 0.0,
-	x: 0,
-	y: 0
-}));
+// Attach the background image to the game
+var background = game.attachAsset('background', {
+	anchorX: 0.5,
+	anchorY: 0.5
+});
+background.x = 2048 / 2;
+background.y = 2732 / 2;
 // Initialize player
 var player = game.addChild(new Player());
 player.x = 2048 / 2;
 player.y = 2732 - 200;