var Plane = Container.expand(function () {
	var self = Container.call(this);
	var planeGraphics = self.createAsset('plane', 'Plane Graphics', .5, .5);
});
var Tower = Container.expand(function () {
	var self = Container.call(this);
	var towerGraphics = self.createAsset('tower', 'Tower Graphics', .5, .5);
	self.shoot = function () {};
});
var Enemy = Container.expand(function () {
	var self = Container.call(this);
	var enemyGraphics = self.createAsset('enemy', 'Enemy Graphics', .5, .5);
	self.move = function () {};
});
var Bullet = Container.expand(function () {
	var self = Container.call(this);
	var bulletGraphics = self.createAsset('bullet', 'Bullet Graphics', .5, .5);
	self.move = function () {};
});
var Game = Container.expand(function () {
	var self = Container.call(this);
	LK.stageContainer.setBackgroundColor(0xFFFFFF);
	var towers = [];
	var enemies = [];
	var bullets = [];
	for (var i = 0; i < 5; i++) {
		var tower = new Tower();
		tower.x = 2048 / 2 + i * 100;
		tower.y = 2732 / 2;
		towers.push(tower);
		self.addChild(tower);
	}
	for (var i = 0; i < 10; i++) {
		var enemy = new Enemy();
		enemy.x = 2048 / 2 + i * 100;
		enemy.y = 2732 / 2 + 200;
		enemies.push(enemy);
		self.addChild(enemy);
	}
	LK.on('tick', function () {
		for (var i = 0; i < towers.length; i++) {
			towers[i].shoot();
		}
		for (var i = 0; i < enemies.length; i++) {
			enemies[i].move();
		}
		for (var i = 0; i < bullets.length; i++) {
			bullets[i].move();
		}
	});
});

===================================================================
--- original.js
+++ change.js
@@ -1,4 +1,8 @@
+var Plane = Container.expand(function () {
+	var self = Container.call(this);
+	var planeGraphics = self.createAsset('plane', 'Plane Graphics', .5, .5);
+});
 var Tower = Container.expand(function () {
 	var self = Container.call(this);
 	var towerGraphics = self.createAsset('tower', 'Tower Graphics', .5, .5);
 	self.shoot = function () {};