/**** 
* 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.shoot = function () {
		var bullet = new HeroBullet();
		bullet.x = self.x;
		bullet.y = self.y - self.height / 2;
		game.addChild(bullet);
		heroBullets.push(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 () {
		self.y += 2;
		if (self.y > 2732 + self.height) {
			self.destroy();
			enemies.splice(enemies.indexOf(self), 1);
		}
	};
});
// HeroBullet class
var HeroBullet = Container.expand(function () {
	var self = Container.call(this);
	var bulletGraphics = self.attachAsset('heroBullet', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	self.move = function () {
		self.y -= 10;
		if (self.y < -self.height) {
			self.destroy();
			heroBullets.splice(heroBullets.indexOf(self), 1);
		}
	};
});
// EnemyBullet class
var EnemyBullet = Container.expand(function () {
	var self = Container.call(this);
	var bulletGraphics = self.attachAsset('enemyBullet', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	self.move = function () {
		self.y += 5;
		if (self.y > 2732 + self.height) {
			self.destroy();
			enemyBullets.splice(enemyBullets.indexOf(self), 1);
		}
	};
});

/**** 
* Initialize Game
****/
var game = new LK.Game({
	backgroundColor: 0x000000 // Init game with black background
});

/**** 
* Game Code
****/
// Define the assets for the hero, enemy robots, and bullets
// Initialize hero
var hero = game.addChild(new Hero());
hero.x = 2048 / 2;
hero.y = 2732 - 100;
// Initialize enemy and bullet arrays
var enemies = [];
var heroBullets = [];
var enemyBullets = [];
// Handle shooting and moving the hero
game.on('down', function (obj) {
	hero.shoot();
});
// Handle swipe
game.on('move', function (obj) {
	var event = obj.event;
	var pos = event.getLocalPosition(game);
	hero.x = pos.x;
});
// Game tick event
LK.on('tick', function () {
	// Move hero bullets
	for (var i = heroBullets.length - 1; i >= 0; i--) {
		heroBullets[i].move();
	}
	// Move enemy bullets
	for (var j = enemyBullets.length - 1; j >= 0; j--) {
		enemyBullets[j].move();
	}
	// Move enemies and randomly shoot
	for (var k = enemies.length - 1; k >= 0; k--) {
		enemies[k].move();
	}
	// Spawn enemies
	if (LK.ticks % 120 == 0) {
		var enemy = new Enemy();
		enemy.x = Math.random() * (2048 - enemy.width) + enemy.width / 2;
		enemy.y = -enemy.height;
		game.addChild(enemy);
		enemies.push(enemy);
	}
	// Check for collisions between hero bullets and enemies
	for (var h = heroBullets.length - 1; h >= 0; h--) {
		for (var e = enemies.length - 1; e >= 0; e--) {
			if (heroBullets[h].intersects(enemies[e])) {
				heroBullets[h].destroy();
				heroBullets.splice(h, 1);
				enemies[e].destroy();
				enemies.splice(e, 1);
				break;
			}
		}
	}
	// Check for collisions between enemy bullets and hero
	for (var eb = enemyBullets.length - 1; eb >= 0; eb--) {
		if (enemyBullets[eb].intersects(hero)) {
			// Flash screen red for 1 second (1000ms) to show damage taken
			LK.effects.flashScreen(0xff0000, 1000);
			// Show game over
			LK.showGameOver();
			break;
		}
	}
});

===================================================================
--- original.js
+++ change.js
@@ -29,15 +29,8 @@
 			self.destroy();
 			enemies.splice(enemies.indexOf(self), 1);
 		}
 	};
-	self.shoot = function () {
-		var bullet = new EnemyBullet();
-		bullet.x = self.x;
-		bullet.y = self.y + self.height / 2;
-		game.addChild(bullet);
-		enemyBullets.push(bullet);
-	};
 });
 // HeroBullet class
 var HeroBullet = Container.expand(function () {
 	var self = Container.call(this);
@@ -110,11 +103,8 @@
 	}
 	// Move enemies and randomly shoot
 	for (var k = enemies.length - 1; k >= 0; k--) {
 		enemies[k].move();
-		if (Math.random() < 0.01) {
-			enemies[k].shoot();
-		}
 	}
 	// Spawn enemies
 	if (LK.ticks % 120 == 0) {
 		var enemy = new Enemy();