var Obstacle = Container.expand(function () {
	var self = Container.call(this);
	var obstacleShadow = self.createAsset('obstacleShadow', 'Obstacle Shadow', .5, .5);
	obstacleShadow.rotation = Math.PI / 4;
	var obstacleShadow2 = self.createAsset('obstacleShadow2', 'Obstacle Shadow 2', .5, .5);
	obstacleShadow2.rotation = Math.PI / 4;
	var obstacleGraphics = self.createAsset('obstacle', 'Obstacle', .5, .5);
	obstacleGraphics.rotation = Math.PI / 4;
	self.speed = 5;
	self.move = function (speed) {
		self.y += speed;
	};
});
var Wall = Container.expand(function () {
	var self = Container.call(this);
	var wallGraphics = self.createAsset('wall', 'Wall', .5, .5);
});
var Bird = Container.expand(function () {
	var self = Container.call(this);
	var birdGraphics = self.createAsset('bird', 'Bird character', .5, .5);
	birdGraphics.scale.x = 1;
	self.xSpeed = 10.9375;
	self.ySpeed = -20;
	self.gravity = 1;
	self.lift = -15;
	self.flap = function () {
		self.ySpeed = self.lift * 1.5;
	};
	self.update = function () {
		self.ySpeed += self.gravity;
		self.y += self.ySpeed;
		self.x += self.xSpeed;
		if (self.y <= 0 || self.y >= 2732) {
			self.speed = -self.speed;
		}
		var targetRotation = Math.atan2(self.ySpeed, self.xSpeed * self.scale.x) / 2;
		birdGraphics.rotation += (targetRotation - birdGraphics.rotation) / 10;
	};
	self.flip = function () {
		self.scale.x *= -1;
	};
});
var Game = Container.expand(function () {
	var self = Container.call(this);
	self.score = 0;
	self.obstacleSpeed = 5;
	self.obstacleSpeedIncrease = 0.005;
	self.checkObstacleCollision = function (obstacles) {
		for (var i = 0; i < obstacles.length; i++) {
			obstacles[i].move();
			var dist = Math.sqrt(Math.pow(bird.x - obstacles[i].x, 2) + Math.pow(bird.y - obstacles[i].y, 2));
			if (dist < 280) {
				LK.showGameOver();
			}
		}
	};
	LK.stageContainer.setBackgroundColor(0xadd8e6);
	var scoreText = new Text2('0', {
		size: 150,
		fill: '#3a84f7',
		font: 'Impact',
		dropShadow: true,
		dropShadowColor: '#222a9a',
		dropShadowBlur: 5,
		dropShadowDistance: 7,
		dropShadowAngle: 0
	});
	scoreText.anchor.set(.5, 0);
	LK.gui.topCenter.addChild(scoreText);
	var bird = self.addChild(new Bird());
	var leftWall = self.addChild(new Wall());
	leftWall.x = 0;
	leftWall.y = 1366;
	var rightWall = self.addChild(new Wall());
	rightWall.x = 2048;
	rightWall.y = 1366;
	var leftObstacles = [], rightObstacles = [];
	var obstacleSpawnRandomness = 120;
	var obstacleSpawnRandomnessDecrease = 0.05;
	var obstacleSpawnY = -500;
	var leftObstacleSpawnTime = Math.floor(Math.random() * obstacleSpawnRandomness) + obstacleSpawnRandomness;
	var rightObstacleSpawnTime = Math.floor(Math.random() * obstacleSpawnRandomness) + obstacleSpawnRandomness;
	bird.x = 1024;
	bird.y = 1366;
	stage.on('down', function (obj) {
		bird.flap();
	});
	LK.on('tick', function () {
		bird.update();
		scoreText.setText(self.score);
		self.obstacleSpeed += self.obstacleSpeedIncrease;
		obstacleSpawnRandomness -= obstacleSpawnRandomnessDecrease;
		if (obstacleSpawnRandomness < 60) {
			obstacleSpawnRandomness = 60;
		}
		if (LK.ticks >= leftObstacleSpawnTime) {
			var newObstacle = self.addChildAt(new Obstacle(), 0);
			newObstacle.x = 0;
			newObstacle.y = obstacleSpawnY;
			leftObstacles.push(newObstacle);
			leftObstacleSpawnTime += Math.floor(Math.random() * obstacleSpawnRandomness) + obstacleSpawnRandomness;
		}
		if (LK.ticks >= rightObstacleSpawnTime) {
			var newObstacle = self.addChildAt(new Obstacle(), 0);
			newObstacle.x = 2048;
			newObstacle.y = -newObstacle.height;
			rightObstacles.push(newObstacle);
			rightObstacleSpawnTime += Math.floor(Math.random() * obstacleSpawnRandomness) + obstacleSpawnRandomness;
		}
		if (bird.intersects(leftWall) && bird.xSpeed < 0 || bird.intersects(rightWall) && bird.xSpeed > 0) {
			bird.xSpeed = -bird.xSpeed;
			bird.flip();
			self.score++;
		}
		for (var i = leftObstacles.length - 1; i >= 0; i--) {
			leftObstacles[i].move(self.obstacleSpeed);
			if (leftObstacles[i].y > 3232) {
				leftObstacles[i].destroy();
				leftObstacles.splice(i, 1);
			}
		}
		for (var i = rightObstacles.length - 1; i >= 0; i--) {
			rightObstacles[i].move(self.obstacleSpeed);
			if (rightObstacles[i].y > 3232) {
				rightObstacles[i].destroy();
				rightObstacles.splice(i, 1);
			}
		}
		self.checkObstacleCollision(leftObstacles);
		self.checkObstacleCollision(rightObstacles);
		if (bird.y < 0 || bird.y > 2732) {
			LK.showGameOver();
		}
	});
});

===================================================================
--- original.js
+++ change.js
@@ -1,12 +1,10 @@
 var Obstacle = Container.expand(function () {
 	var self = Container.call(this);
 	var obstacleShadow = self.createAsset('obstacleShadow', 'Obstacle Shadow', .5, .5);
 	obstacleShadow.rotation = Math.PI / 4;
-	obstacleShadow.y = 15;
 	var obstacleShadow2 = self.createAsset('obstacleShadow2', 'Obstacle Shadow 2', .5, .5);
 	obstacleShadow2.rotation = Math.PI / 4;
-	obstacleShadow2.y = -7;
 	var obstacleGraphics = self.createAsset('obstacle', 'Obstacle', .5, .5);
 	obstacleGraphics.rotation = Math.PI / 4;
 	self.speed = 5;
 	self.move = function (speed) {