var SmallEnemy = Container.expand(function () {
	var self = Container.call(this);
	var enemyGraphics = self.createAsset('smallEnemy', 'Small Enemy character', .5, .5);
	self.followHero = function (hero) {
		var dx = hero.x - self.x;
		var dy = hero.y - self.y;
		var mag = Math.sqrt(dx * dx + dy * dy);
		self.x += 3.85 * dx / mag;
		self.y += 3.85 * dy / mag;
	};
});
var HeroBullet = Container.expand(function () {
	var self = Container.call(this);
	var bulletGraphics = self.createAsset('heroBullet', 'Hero Bullet Graphics', .5, .5);
	self.speed = -10;
	self.move = function () {
		self.x += self.speedX;
		self.y += self.speedY;
	};
	self.timer = LK.setTimeout(function () {
		self.destroy();
	}, 5000);
});
var EnemyBullet = Container.expand(function () {
	var self = Container.call(this);
	var bulletGraphics = self.createAsset('enemyBullet', 'Enemy Bullet Graphics', .5, .5);
	self.speed = 10;
	self.move = function () {
		self.x += self.speed;
	};
	self.timer = LK.setTimeout(function () {
		self.destroy();
	}, 5000);
});
var Hero = Container.expand(function () {
	var self = Container.call(this);
	self.update = function () {
		if (self.dx && self.dy) {
			self.x -= self.dx;
			self.y -= self.dy;
			self.dx *= 0.99;
			self.dy *= 0.99;
			if (Math.abs(self.dx) < 0.01 && Math.abs(self.dy) < 0.01) {
				self.dx = 0;
				self.dy = 0;
			}
		}
	};
	var heroGraphics = self.createAsset('hero', 'Hero character', .5, .5);
	self.knockback = function (dx, dy) {
		self.dx = -dx * 116.886;
		self.dy = -dy * 116.886;
	};
});
var Enemy = Container.expand(function () {
	var self = Container.call(this);
	var enemyGraphics = self.createAsset('enemy', 'Enemy character', .5, .5);
	self.followHero = function (hero) {
		var dx = hero.x - self.x;
		var dy = hero.y - self.y;
		var mag = Math.sqrt(dx * dx + dy * dy);
		self.x += 3.85 * dx / mag;
		self.y += 3.85 * dy / mag;
	};
	self.split = function () {
		var smallEnemy1 = new SmallEnemy();
		smallEnemy1.x = self.x;
		smallEnemy1.y = self.y;
		var smallEnemy2 = new SmallEnemy();
		smallEnemy2.x = self.x;
		smallEnemy2.y = self.y;
		var smallEnemy3 = new SmallEnemy();
		smallEnemy3.x = self.x;
		smallEnemy3.y = self.y;
		var smallEnemy4 = new SmallEnemy();
		smallEnemy4.x = self.x;
		smallEnemy4.y = self.y;
		var smallEnemy5 = new SmallEnemy();
		smallEnemy5.x = self.x;
		smallEnemy5.y = self.y;
		self.parent.addChild(smallEnemy1);
		self.parent.addChild(smallEnemy2);
		self.parent.addChild(smallEnemy3);
		self.parent.addChild(smallEnemy4);
		self.parent.addChild(smallEnemy5);
		self.destroy();
	};
});
var Game = Container.expand(function () {
	var self = Container.call(this);
	LK.stageContainer.setBackgroundColor(0x000000);
	var hero = self.addChild(new Hero());
	var enemy = self.addChild(new Enemy());
	hero.x = 1024;
	hero.y = 1366;
	enemy.x = 1024;
	enemy.y = 1366 - 200;
	var heroBullets = [];
	var enemyBullets = [];
	var smallEnemies = [];
	var isGameOver = false;
	var tickOffset = 0;
	var fpsCounter = new Text2('0', {
		size: 50,
		fill: '#ffffff'
	});
	LK.gui.topCenter.addChild(fpsCounter);
	var lastTick = Date.now();
	var frameCount = 0;
	LK.on('tick', function () {
		if (isGameOver) {
			LK.effects.flashScreen(0xff0000, 1000);
			LK.showGameOver();
		}
		frameCount++;
		var now = Date.now();
		if (now - lastTick >= 1000) {
			fpsCounter.setText(frameCount);
			frameCount = 0;
			lastTick = now;
		}
		hero.update();
		enemy.followHero(hero);
		for (var i = 0; i < smallEnemies.length; i++) {
			smallEnemies[i].followHero(hero);
		}
		for (var a = heroBullets.length - 1; a >= 0; a--) {
			heroBullets[a].move();
			if (heroBullets[a].y < -50 || heroBullets[a].y > 2732 + 50 || heroBullets[a].x < -50 || heroBullets[a].x > 2048 + 50) {
				heroBullets[a].destroy();
				heroBullets.splice(a, 1);
			} else if (heroBullets[a] && heroBullets[a].intersects(enemy)) {
				enemy.split();
				heroBullets[a].destroy();
				heroBullets.splice(a, 1);
			}
		}
		for (var a = enemyBullets.length - 1; a >= 0; a--) {
			if (enemyBullets[a]) {
				enemyBullets[a].move();
				if (enemyBullets[a].y > 2732 + 50) {
					enemyBullets[a].destroy();
					enemyBullets.splice(a, 1);
				}
			}
		}
		var lastShot = 0;
		var bulletCount = 0;
		stage.on('down', function (obj) {
			var event = obj.event;
			var pos = event.getLocalPosition(self);
			var newBullet = new HeroBullet();
			newBullet.x = hero.x;
			newBullet.y = hero.y;
			var dx = pos.x - hero.x;
			var dy = pos.y - hero.y;
			var mag = Math.sqrt(dx * dx + dy * dy);
			newBullet.speedX = 10 * dx / mag;
			newBullet.speedY = 10 * dy / mag;
			heroBullets.push(newBullet);
			self.addChild(newBullet);
			hero.knockback(-dx / (mag * 10), -dy / (mag * 10));
		});
		LK.on('tick', function () {
			if (bulletCount > 0) bulletCount--;
		});
	});
});

===================================================================
--- original.js
+++ change.js
@@ -61,9 +61,9 @@
 		var mag = Math.sqrt(dx * dx + dy * dy);
 		self.x += 3.85 * dx / mag;
 		self.y += 3.85 * dy / mag;
 	};
-	self.split = function (gameInstance) {
+	self.split = function () {
 		var smallEnemy1 = new SmallEnemy();
 		smallEnemy1.x = self.x;
 		smallEnemy1.y = self.y;
 		var smallEnemy2 = new SmallEnemy();
@@ -77,13 +77,13 @@
 		smallEnemy4.y = self.y;
 		var smallEnemy5 = new SmallEnemy();
 		smallEnemy5.x = self.x;
 		smallEnemy5.y = self.y;
-		gameInstance.addChild(smallEnemy1);
-		gameInstance.addChild(smallEnemy2);
-		gameInstance.addChild(smallEnemy3);
-		gameInstance.addChild(smallEnemy4);
-		gameInstance.addChild(smallEnemy5);
+		self.parent.addChild(smallEnemy1);
+		self.parent.addChild(smallEnemy2);
+		self.parent.addChild(smallEnemy3);
+		self.parent.addChild(smallEnemy4);
+		self.parent.addChild(smallEnemy5);
 		self.destroy();
 	};
 });
 var Game = Container.expand(function () {