===================================================================
--- original.js
+++ change.js
@@ -1,41 +1,38 @@
 /**** 
 * Classes
 ****/ 
-// Bullet class
-var Bullet = Container.expand(function () {
+var Enemy = Container.expand(function () {
 	var self = Container.call(this);
-	var bulletGraphics = self.attachAsset('bullet', {
+	var enemyGraphics = self.attachAsset('enemy', {
 		anchorX: 0.5,
 		anchorY: 0.5
 	});
 	self.speed = -5;
 	self.update = function () {
 		self.y += self.speed;
+		if (self.y < -enemyGraphics.height) {
+			self.destroy();
+		}
 	};
 });
-// Car class
-var Car = Container.expand(function () {
+var Player = Container.expand(function () {
 	var self = Container.call(this);
-	var carGraphics = self.attachAsset('car', {
+	var playerGraphics = self.attachAsset('car', {
 		anchorX: 0.5,
 		anchorY: 0.5
 	});
 	self.speed = 5;
 	self.update = function () {
-		self.y += self.speed;
+		if (self.y < 0) {
+			self.y = 0;
+		}
+		if (self.y > 2732 - playerGraphics.height) {
+			self.y = 2732 - playerGraphics.height;
+		}
 	};
-});
-// Enemy class
-var Enemy = Container.expand(function () {
-	var self = Container.call(this);
-	var enemyGraphics = self.attachAsset('enemy', {
-		anchorX: 0.5,
-		anchorY: 0.5
-	});
-	self.speed = 2;
-	self.update = function () {
-		self.y += self.speed;
+	self.move = function (x, y, obj) {
+		self.y = y;
 	};
 });
 
 /**** 
@@ -47,56 +44,24 @@
 
 /**** 
 * Game Code
 ****/ 
-// Initialize the car
-var car = game.addChild(new Car());
-car.x = 2048 / 2;
-car.y = 2732 - 100;
-// Initialize the bullets
-var bullets = [];
-// Initialize the enemies
+var player = game.addChild(new Player());
+player.x = 2048 / 2;
+player.y = 2732 / 2;
 var enemies = [];
-for (var i = 0; i < 10; i++) {
-	var enemy = game.addChild(new Enemy());
-	enemy.x = Math.random() * 2048;
-	enemy.y = Math.random() * 500;
-	enemies.push(enemy);
-}
-// Initialize LK.keys object
-LK.keys = {
-	'ArrowLeft': false,
-	'ArrowRight': false,
-	'Space': false
-};
 game.update = function () {
-	// Move the car
-	if (LK.keys['ArrowLeft']) {
-		car.x -= car.speed;
+	if (LK.ticks % 30 == 0) {
+		var newEnemy = new Enemy();
+		newEnemy.x = Math.random() * 2048;
+		newEnemy.y = 2732;
+		enemies.push(newEnemy);
+		game.addChild(newEnemy);
 	}
-	if (LK.keys['ArrowRight']) {
-		car.x += car.speed;
-	}
-	// Shoot bullets
-	if (LK.keys['Space']) {
-		var bullet = game.addChild(new Bullet());
-		bullet.x = car.x;
-		bullet.y = car.y;
-		bullets.push(bullet);
-		LK.getSound('shoot').play();
-	}
-	// Check for collisions
-	for (var i = bullets.length - 1; i >= 0; i--) {
-		var bullet = bullets[i];
-		for (var j = enemies.length - 1; j >= 0; j--) {
-			var enemy = enemies[j];
-			if (bullet.intersects(enemy)) {
-				bullet.destroy();
-				bullets.splice(i, 1);
-				enemy.destroy();
-				enemies.splice(j, 1);
-				LK.getSound('enemyDestroyed').play();
-				break;
-			}
+	for (var i = enemies.length - 1; i >= 0; i--) {
+		if (player.intersects(enemies[i])) {
+			LK.getSound('enemyDestroyed').play();
+			enemies[i].destroy();
+			enemies.splice(i, 1);
 		}
 	}
 };
\ No newline at end of file