===================================================================
--- original.js
+++ change.js
@@ -1,61 +1,61 @@
-/****
+/**** 
 * Classes
-****/
+****/ 
 // Bullet class
 var Bullet = Container.expand(function () {
-  var self = Container.call(this);
-  var bulletGraphics = self.attachAsset('bullet', {
-    anchorX: 0.5,
-    anchorY: 0.5
-  });
-  self.speed = -15;
-  self.update = function () {
-    self.y += self.speed;
-    if (self.y < 0) {
-      self.destroy();
-    }
-  };
+	var self = Container.call(this);
+	var bulletGraphics = self.attachAsset('bullet', {
+		anchorX: 0.5,
+		anchorY: 0.5
+	});
+	self.speed = -20;
+	self.update = function () {
+		self.y += self.speed;
+		if (self.y < 0) {
+			self.destroy();
+		}
+	};
 });
 // Assets will be automatically created and loaded during gameplay
 // Hero class
 var Hero = Container.expand(function () {
-  var self = Container.call(this);
-  var heroGraphics = self.attachAsset('hero', {
-    anchorX: 0.5,
-    anchorY: 0.5
-  });
-  self.speed = 10;
-  self.update = function () {
-    // Hero update logic
-  };
+	var self = Container.call(this);
+	var heroGraphics = self.attachAsset('hero', {
+		anchorX: 0.5,
+		anchorY: 0.5
+	});
+	self.speed = 10;
+	self.update = function () {
+		// Hero update logic
+	};
 });
 // Zombie class
 var Zombie = Container.expand(function () {
-  var self = Container.call(this);
-  var zombieGraphics = self.attachAsset('zombie', {
-    anchorX: 0.5,
-    anchorY: 0.5
-  });
-  self.speed = 2;
-  self.update = function () {
-    self.y += self.speed;
-    if (self.y > 2732) {
-      self.destroy();
-    }
-  };
+	var self = Container.call(this);
+	var zombieGraphics = self.attachAsset('zombie', {
+		anchorX: 0.5,
+		anchorY: 0.5
+	});
+	self.speed = 2;
+	self.update = function () {
+		self.y += self.speed;
+		if (self.y > 2732) {
+			self.destroy();
+		}
+	};
 });
 
-/****
+/**** 
 * Initialize Game
-****/
+****/ 
 var game = new LK.Game({
-  backgroundColor: 0x000000 // Init game with black background
+	backgroundColor: 0x000000 // Init game with black background
 });
 
-/****
+/**** 
 * Game Code
-****/
+****/ 
 // Initialize variables
 var hero;
 var zombies = [];
 var bullets = [];
@@ -66,58 +66,59 @@
 hero.x = 2048 / 2;
 hero.y = 2732 - 200;
 // Initialize score text
 scoreTxt = new Text2('0', {
-  size: 150,
-  fill: "#ffffff"
+	size: 150,
+	fill: "#ffffff"
 });
 scoreTxt.anchor.set(0.5, 0);
 LK.gui.top.addChild(scoreTxt);
 // Handle game move events
 game.move = function (x, y, obj) {
-  hero.x = x;
-  hero.y = y;
+	hero.x = x;
+	hero.y = y;
 };
 // Handle game down events
 game.down = function (x, y, obj) {
-  var bullet = new Bullet();
-  bullet.x = hero.x;
-  bullet.y = hero.y;
-  bullets.push(bullet);
-  game.addChild(bullet);
+	var bullet = new Bullet();
+	bullet.x = hero.x;
+	bullet.y = hero.y;
+	bullets.push(bullet);
+	game.addChild(bullet);
+	LK.getSound('shoot').play();
 };
 // Update game logic
 game.update = function () {
-  // Update hero
-  hero.update();
-  // Update zombies
-  for (var i = zombies.length - 1; i >= 0; i--) {
-    zombies[i].update();
-    if (zombies[i].intersects(hero)) {
-      LK.effects.flashScreen(0xff0000, 1000);
-      LK.showGameOver();
-    }
-  }
-  // Update bullets
-  for (var j = bullets.length - 1; j >= 0; j--) {
-    bullets[j].update();
-    for (var k = zombies.length - 1; k >= 0; k--) {
-      if (bullets[j].intersects(zombies[k])) {
-        bullets[j].destroy();
-        bullets.splice(j, 1);
-        zombies[k].destroy();
-        zombies.splice(k, 1);
-        score++;
-        scoreTxt.setText(score);
-        break;
-      }
-    }
-  }
-  // Spawn new zombies
-  if (LK.ticks % 60 == 0) {
-    var zombie = new Zombie();
-    zombie.x = Math.random() * 2048;
-    zombie.y = -100;
-    zombies.push(zombie);
-    game.addChild(zombie);
-  }
+	// Update hero
+	hero.update();
+	// Update zombies
+	for (var i = zombies.length - 1; i >= 0; i--) {
+		zombies[i].update();
+		if (zombies[i].intersects(hero)) {
+			LK.effects.flashScreen(0xff0000, 1000);
+			LK.showGameOver();
+		}
+	}
+	// Update bullets
+	for (var j = bullets.length - 1; j >= 0; j--) {
+		bullets[j].update();
+		for (var k = zombies.length - 1; k >= 0; k--) {
+			if (bullets[j].intersects(zombies[k])) {
+				bullets[j].destroy();
+				bullets.splice(j, 1);
+				zombies[k].destroy();
+				zombies.splice(k, 1);
+				score++;
+				scoreTxt.setText(score);
+				break;
+			}
+		}
+	}
+	// Spawn new zombies
+	if (LK.ticks % 60 == 0) {
+		var zombie = new Zombie();
+		zombie.x = Math.random() * 2048;
+		zombie.y = -100;
+		zombies.push(zombie);
+		game.addChild(zombie);
+	}
 };
\ No newline at end of file