/**** 
* 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;
	};
});
// 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 = 5;
	self.update = function () {
		self.y += self.speed;
		if (self.y > 2732) {
			self.y = 0;
			self.x = Math.random() * 2048;
		}
	};
});
//<Assets used in the game will automatically appear here>
//<Write imports for supported plugins here>
// 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
	};
});

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

/**** 
* Game Code
****/ 
// Initialize hero
var hero = game.addChild(new Hero());
hero.x = 1024;
hero.y = 2500;
// Initialize enemies
var enemies = [];
for (var i = 0; i < 5; i++) {
	var enemy = new Enemy();
	enemy.x = Math.random() * 2048;
	enemy.y = Math.random() * 1000;
	enemies.push(enemy);
	game.addChild(enemy);
}
// Initialize bullets
var bullets = [];
// Handle game move event
game.move = function (x, y, obj) {
	hero.x = x;
	hero.y = y;
};
game.down = function (x, y, obj) {
	var newBullet = new Bullet();
	newBullet.x = hero.x;
	newBullet.y = hero.y;
	bullets.push(newBullet);
	game.addChild(newBullet);
};
// Handle game update event
game.update = function () {
	// Update bullets
	for (var i = bullets.length - 1; i >= 0; i--) {
		var bullet = bullets[i];
		bullet.update();
		if (bullet.y < 0) {
			bullet.destroy();
			bullets.splice(i, 1);
		}
	}
	// Update enemies
	for (var j = enemies.length - 1; j >= 0; j--) {
		var enemy = enemies[j];
		enemy.update();
		if (hero.intersects(enemy)) {
			LK.effects.flashScreen(0xff0000, 1000);
			LK.showGameOver();
		}
		// Check for bullet collision
		for (var k = bullets.length - 1; k >= 0; k--) {
			var bullet = bullets[k];
			if (bullet.intersects(enemy)) {
				// Destroy bullet and enemy
				bullet.destroy();
				bullets.splice(k, 1);
				enemy.destroy();
				enemies.splice(j, 1);
				break;
			}
		}
	}
	// Fire bullets
	if (LK.ticks % 20 == 0) {
		var newBullet = new Bullet();
		newBullet.x = hero.x;
		newBullet.y = hero.y;
		bullets.push(newBullet);
		game.addChild(newBullet);
	}
};

===================================================================
--- original.js
+++ change.js
@@ -73,8 +73,15 @@
 game.move = function (x, y, obj) {
 	hero.x = x;
 	hero.y = y;
 };
+game.down = function (x, y, obj) {
+	var newBullet = new Bullet();
+	newBullet.x = hero.x;
+	newBullet.y = hero.y;
+	bullets.push(newBullet);
+	game.addChild(newBullet);
+};
 // Handle game update event
 game.update = function () {
 	// Update bullets
 	for (var i = bullets.length - 1; i >= 0; i--) {