===================================================================
--- original.js
+++ change.js
@@ -1,147 +1,19 @@
-/****
-* Classes
-****/
-// Hero class
-var Hero = Container.expand(function () {
-  var self = Container.call(this);
-  var heroGraphics = self.attachAsset('hero', {
-    anchorX: 0.5,
-    anchorY: 0.5
-  });
-  self.move = function (x, y) {
-    self.x = x;
-    self.y = y;
-  };
-  self.shoot = function () {
-    var bullet = new HeroBullet();
-    bullet.x = self.x;
-    bullet.y = self.y;
-    game.addChild(bullet);
-    return bullet;
-  };
-});
-// Enemy class
-var Enemy = Container.expand(function () {
-  var self = Container.call(this);
-  var enemyGraphics = self.attachAsset('enemy', {
-    anchorX: 0.5,
-    anchorY: 0.5
-  });
-  self.move = function () {
-    // Enemy movement logic
-  };
-  self.shoot = function () {
-    var bullet = new EnemyBullet();
-    bullet.x = self.x;
-    bullet.y = self.y;
-    game.addChild(bullet);
-    return bullet;
-  };
-});
-// HeroBullet class
-var HeroBullet = Container.expand(function () {
-  var self = Container.call(this);
-  var bulletGraphics = self.attachAsset('heroBullet', {
-    anchorX: 0.5,
-    anchorY: 0.5
-  });
-  self.speed = 5;
-  self.move = function () {
-    self.y -= self.speed;
-  };
-});
-// EnemyBullet class
-var EnemyBullet = Container.expand(function () {
-  var self = Container.call(this);
-  var bulletGraphics = self.attachAsset('enemyBullet', {
-    anchorX: 0.5,
-    anchorY: 0.5
-  });
-  self.speed = 3;
-  self.move = function () {
-    self.y += self.speed;
-  };
-});
-// Base class
-var Base = Container.expand(function () {
-  var self = Container.call(this);
-  var baseGraphics = self.attachAsset('base', {
-    anchorX: 0.5,
-    anchorY: 0.5
-  });
-});
-
-/****
+/**** 
 * Initialize Game
 ****/
 var game = new LK.Game({
-  backgroundColor: 0x000000 // Init game with black background 
+	backgroundColor: 0x000000 // Init game with black background 
 });
 
-/****
+/**** 
 * Game Code
 ****/
-// Initialize game elements
 // Initialize assets used in this game.
-var hero = game.addChild(new Hero());
-hero.x = game.width / 2;
-hero.y = game.height - hero.height;
-var enemies = [];
-for (var i = 0; i < 5; i++) {
-  var enemy = game.addChild(new Enemy());
-  enemy.x = 100 + i * 150;
-  enemy.y = 100;
-  enemies.push(enemy);
-}
-var heroBullets = [];
-var enemyBullets = [];
-var base = game.addChild(new Base());
-base.x = game.width / 2;
-base.y = game.height - base.height / 2;
+// Initialize game elements
 // Event listeners
 game.on('down', function (obj) {
-  var pos = obj.event.getLocalPosition(game);
-  hero.move(pos.x, pos.y);
+	var pos = obj.event.getLocalPosition(game);
 });
-game.on('up', function (obj) {
-  heroBullets.push(hero.shoot());
-});
+game.on('up', function (obj) {});
 // Game tick
-LK.on('tick', function () {
-  // Move hero bullets
-  for (var i = heroBullets.length - 1; i >= 0; i--) {
-    heroBullets[i].move();
-    if (heroBullets[i].y < 0) {
-      heroBullets[i].destroy();
-      heroBullets.splice(i, 1);
-    }
-  }
-  // Move enemy bullets
-  for (var j = enemyBullets.length - 1; j >= 0; j--) {
-    enemyBullets[j].move();
-    if (enemyBullets[j].y > game.height) {
-      enemyBullets[j].destroy();
-      enemyBullets.splice(j, 1);
-    }
-  }
-  // Enemy actions
-  for (var k = 0; k < enemies.length; k++) {
-    enemies[k].move();
-    if (LK.ticks % 120 === 0) {
-      // Every 2 seconds
-      enemyBullets.push(enemies[k].shoot());
-    }
-  }
-  // Collision detection
-  for (var l = heroBullets.length - 1; l >= 0; l--) {
-    for (var m = enemies.length - 1; m >= 0; m--) {
-      if (heroBullets[l].intersects(enemies[m])) {
-        heroBullets[l].destroy();
-        heroBullets.splice(l, 1);
-        enemies[m].destroy();
-        enemies.splice(m, 1);
-        break;
-      }
-    }
-  }
-});
\ No newline at end of file
+LK.on('tick', function () {});
\ No newline at end of file