var Player = Container.expand(function () {
	var self = Container.call(this);
	var playerGraphics = self.createAsset('player_hands', 'Player Hands Graphics', .5, 1);
	self.x = 2048 / 2;
	self.y = 2732;
});
var Shuriken = Container.expand(function () {
	var self = Container.call(this);
	var shurikenGraphics = self.createAsset('shuriken', 'Shuriken Graphics', .5, .5);
	self.speed = 5;
	self.move = function () {};
	self.destroy = function () {};
});
var Rat = Container.expand(function () {
	var self = Container.call(this);
	var ratGraphics = self.createAsset('rat', 'Rat Graphics', .5, .5);
	self.speed = -2;
	self.move = function () {
		self.y -= self.speed;
	};
	self.destroy = function () {};
});
var PowerUp = Container.expand(function () {
	var self = Container.call(this);
	var powerUpGraphics = self.createAsset('powerUp', 'PowerUp Graphics', .5, .5);
	self.activate = function () {};
});
var Game = Container.expand(function () {
	var self = Container.call(this);
	var background = self.createAsset('wooden_floor', 'Level Background', 0, 0);
	background.width = 2048;
	background.height = 2732;
	var scoreTxt = new Text2('0', {
		size: 150,
		fill: "#ffffff"
	});
	scoreTxt.anchor.set(.5, 0);
	LK.gui.topCenter.addChild(scoreTxt);
	var player = new Player();
	self.addChild(player);
	var shurikens = [];
	var rats = [];
	var powerUps = [];
	var isGameOver = false;
	var tickOffset = 0;
	var score = 0;
	var isDragging = false;
	var dragStartPos = {
		x: 0,
		y: 0
	};
	function init() {
		LK.setInterval(function () {
			var rat = new Rat();
			rat.x = Math.random() * 2048;
			rat.y = 0;
			rats.push(rat);
			self.addChild(rat);
		}, Math.random() * 2000 + 1000);
	}
	function update() {
		for (var i = 0; i < rats.length; i++) {
			rats[i].move();
			if (rats[i].y >= 2732) {
				isGameOver = true;
				break;
			}
		}
	}
	function gameOver() {
		LK.showGameOver();
	}
	function checkCollision() {
		for (var i = 0; i < shurikens.length; i++) {
			for (var j = 0; j < rats.length; j++) {
				if (shurikens[i].intersects(rats[j])) {
					shurikens[i].destroy();
					shurikens.splice(i, 1);
					rats[j].destroy();
					rats.splice(j, 1);
					score++;
					break;
				}
			}
		}
	}
	function updateScore() {
		scoreTxt.setText(score);
	}
	stage.on('down', function (obj) {
		isDragging = true;
		dragStartPos = obj.event.getLocalPosition(self);
	});
	stage.on('move', function (obj) {});
	stage.on('up', function (obj) {
		if (isDragging) {
			isDragging = false;
			var dragEndPos = obj.event.getLocalPosition(self);
			var direction = {
				x: dragEndPos.x - dragStartPos.x,
				y: dragEndPos.y - dragStartPos.y
			};
			var shuriken = new Shuriken();
			shuriken.x = player.x;
			shuriken.y = player.y;
			shuriken.move = function () {
				this.x += direction.x * this.speed;
				this.y += direction.y * this.speed;
			};
			shurikens.push(shuriken);
			self.addChild(shuriken);
		}
	});
	LK.on('tick', function () {
		update();
		checkCollision();
		updateScore();
		if (isGameOver) {
			gameOver();
		}
	});
	init();
});

===================================================================
--- original.js
+++ change.js
@@ -43,8 +43,13 @@
 	var powerUps = [];
 	var isGameOver = false;
 	var tickOffset = 0;
 	var score = 0;
+	var isDragging = false;
+	var dragStartPos = {
+		x: 0,
+		y: 0
+	};
 	function init() {
 		LK.setInterval(function () {
 			var rat = new Rat();
 			rat.x = Math.random() * 2048;
@@ -81,11 +86,32 @@
 	}
 	function updateScore() {
 		scoreTxt.setText(score);
 	}
-	stage.on('down', function (obj) {});
+	stage.on('down', function (obj) {
+		isDragging = true;
+		dragStartPos = obj.event.getLocalPosition(self);
+	});
 	stage.on('move', function (obj) {});
-	stage.on('up', function (obj) {});
+	stage.on('up', function (obj) {
+		if (isDragging) {
+			isDragging = false;
+			var dragEndPos = obj.event.getLocalPosition(self);
+			var direction = {
+				x: dragEndPos.x - dragStartPos.x,
+				y: dragEndPos.y - dragStartPos.y
+			};
+			var shuriken = new Shuriken();
+			shuriken.x = player.x;
+			shuriken.y = player.y;
+			shuriken.move = function () {
+				this.x += direction.x * this.speed;
+				this.y += direction.y * this.speed;
+			};
+			shurikens.push(shuriken);
+			self.addChild(shuriken);
+		}
+	});
 	LK.on('tick', function () {
 		update();
 		checkCollision();
 		updateScore();