/**** 
* Classes
****/ 
// Bullet class
var Bullet = Container.expand(function () {
	var self = Container.call(this);
	// Attach bullet asset
	var bulletGraphics = self.attachAsset('bullet', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	// Set bullet speed
	self.speed = -5;
	// Update function called every game tick
	self.update = function () {
		// Move bullet based on speed
		self.y += self.speed;
	};
});
// Enemy class
var Enemy = Container.expand(function () {
	var self = Container.call(this);
	// Attach enemy asset
	var enemyGraphics = self.attachAsset('enemy', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	// Set enemy speed
	self.speed = 5;
	// Update function called every game tick
	self.update = function () {
		// Move enemy towards the player
		if (self.y < player.y) {
			self.y += self.speed;
		} else {
			self.y -= self.speed;
		}
		if (self.x < player.x) {
			self.x += self.speed;
		} else {
			self.x -= self.speed;
		}
	};
});
// Player class
var Player = Container.expand(function () {
	var self = Container.call(this);
	// Attach player asset
	var playerGraphics = self.attachAsset('player', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	// Set player speed
	self.speed = 5;
	// Update function called every game tick
	self.update = function () {
		// Move player based on speed
		self.x += self.speed;
	};
});

/**** 
* Initialize Game
****/ 
//<Assets used in the game will automatically appear here>
//<Write imports for supported plugins here>
var game = new LK.Game({
	backgroundColor: 0x000000
});

/**** 
* Game Code
****/ 
game.down = function (x, y, obj) {
	// Create a bullet instance
	var bullet = game.addChild(new Bullet());
	// Set bullet initial position
	bullet.x = player.x;
	bullet.y = player.y;
};
var player = game.addChild(new Player());
// Set player initial position
player.x = 1024;
player.y = 2732 - player.height / 2 - 100;
// Create an enemy instance
var enemy = game.addChild(new Enemy());
// Set enemy initial position
enemy.x = 1024;
enemy.y = 0;
// Add mouse move event to the game
game.move = function (x, y, obj) {
	// Move player to mouse position
	player.x = x;
};

===================================================================
--- original.js
+++ change.js
@@ -16,8 +16,33 @@
 		// Move bullet based on speed
 		self.y += self.speed;
 	};
 });
+// Enemy class
+var Enemy = Container.expand(function () {
+	var self = Container.call(this);
+	// Attach enemy asset
+	var enemyGraphics = self.attachAsset('enemy', {
+		anchorX: 0.5,
+		anchorY: 0.5
+	});
+	// Set enemy speed
+	self.speed = 5;
+	// Update function called every game tick
+	self.update = function () {
+		// Move enemy towards the player
+		if (self.y < player.y) {
+			self.y += self.speed;
+		} else {
+			self.y -= self.speed;
+		}
+		if (self.x < player.x) {
+			self.x += self.speed;
+		} else {
+			self.x -= self.speed;
+		}
+	};
+});
 // Player class
 var Player = Container.expand(function () {
 	var self = Container.call(this);
 	// Attach player asset
@@ -56,8 +81,13 @@
 var player = game.addChild(new Player());
 // Set player initial position
 player.x = 1024;
 player.y = 2732 - player.height / 2 - 100;
+// Create an enemy instance
+var enemy = game.addChild(new Enemy());
+// Set enemy initial position
+enemy.x = 1024;
+enemy.y = 0;
 // Add mouse move event to the game
 game.move = function (x, y, obj) {
 	// Move player to mouse position
 	player.x = x;