Help: Problem with function for create in update

http://www.html5gamedevs.com/topic/18107-problem-with-function-for-create-in-update/

by chongdashu

HTML

<script src="https://cdnjs.cloudflare.com/ajax/libs/phaser/2.4.4/phaser.js"></script>

JavaScript

var theGame = function (game) {
    this.upKey;
    this.downKey;
    this.leftKey;
    this.rightKey;

    this.playerCanMove = true;

    this.map;
    this.layer;
    this.layer2;
    this.cursors;
    this.gratz;
    this.playerSprite;
    this.enemy1Sprite;

    this.enemies;

    this.speed = 300;

}

theGame.prototype = {

    preload: function () {
        this.game.load.crossOrigin = 'anonymous';
        this.game.load.image("tiles", "http://imgur.com/9ElFSZR.png");
        this.game.load.image("player", "http://imgur.com/oS5Q1Jx.png");
    },
    create: function () {



        this.player = {
            name: 'Kirito',
            lvl: 1,
            lvl2: false,
            lvl3: false,
            hp: 100,
            attack: 10,
            exp: 10,
            card: 1,
            gold: 0
        }

        this.monsterLvl1 = {
            name: 'Rat',
            hp: 50,
            attack: 5,
            exp: 50,
            gold: 5
        }


        // map = this.game.add.tilemap('MyTerrain');
        //map.addTilesetImage('tiles', 'tiles');
        //map.addTilesetImage('tile2','tile2');
        //map.addTilesetImage('tile3','tile3');

        //map.setCollision(400);

        //layer = map.createLayer('MyTerrain');
        //layer.resizeWorld();
        //layer.wrap false - mapa sie nie powiela przy za duzym oknie gry
        //layer.wrap = false;


        //Kolizja ze wszystkim na warstwie topLayer w zmiennej layer2
        //map.setCollisionBetween(1, 10000, true, layer2);



        playerSprite = this.game.add.sprite(500, 850, 'player');
        enemy1Sprite = this.game.add.sprite(680, 150, 'enemy1');
        //monsterLvl1Sprite = this.game.add.sprite(500,500, 'monsterLvl1');


        //Skalowanie 1.4 dla grafik postaci 32x32
        //monsterLvl1Sprite.scale.setTo(1.4);
        playerSprite.scale.setTo(1.4);



        enemies = this.game.add.group();
        for (var i = 0; i < 16; i++) {
            enemies.create(360 +...