/**** 
* Classes
****/ 
var Bird = Container.expand(function () {
	var self = Container.call(this);
	var birdGraphics = self.attachAsset('bird', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	// Flip the bird horizontally so it faces left initially
	self.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;
		LK.getSound('flap').play();
	};
	self._update_migrated = function () {
		if (game.isMouseDown) {
			self.ySpeed += self.gravity / 3;
		} else {
			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;
	};
});
// Egg class
var Egg = Container.expand(function () {
	var self = Container.call(this);
	var eggGraphics = self.attachAsset('particle', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	self.ySpeed = 8;
	self.update = function () {
		self.y += self.ySpeed;
		// Remove egg if it falls out of screen
		if (self.y > 2800) {
			self.destroy();
			if (game.eggs) {
				var idx = game.eggs.indexOf(self);
				if (idx !== -1) game.eggs.splice(idx, 1);
			}
		}
	};
});
var Obstacle = Container.expand(function () {
	var self = Container.call(this);
	var obstacleShadow = self.attachAsset('obstacleShadow', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	obstacleShadow.rotation = Math.PI / 4;
	var obstacleShadow2 = self.attachAsset('obstacleShadow2', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	obstacleShadow2.rotation = Math.PI / 4;
	obstacleShadow2.y = -7;
	var obstacleGraphics = self.attachAsset('obstacle', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	obstacleGraphics.rotation = Math.PI / 4;
	self.speed = 5;
	self._move_migrated = function (speed) {
		self.y += speed;
	};
});
var Wall = Container.expand(function () {
	var self = Container.call(this);
	var wallGraphics = self.attachAsset('wall', {
		anchorX: 0.5,
		anchorY: 0.5
	});
});

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

/**** 
* Game Code
****/ 
var tutorialTextWhite = new Text2('Tap to Flap\nHold to Float', {
	size: 150,
	fill: '#ffffff',
	font: 'Impact',
	align: 'center'
});
tutorialTextWhite.anchor.set(.5, 1);
tutorialTextWhite.x = -4;
tutorialTextWhite.y = -62;
LK.gui.bottom.addChild(tutorialTextWhite);
var tutorialText = new Text2('Tap to Flap\nHold to Float', {
	size: 150,
	fill: '#3a84f7',
	font: 'Impact',
	dropShadow: true,
	dropShadowColor: '#222a9a',
	dropShadowBlur: 5,
	dropShadowDistance: 7,
	dropShadowAngle: 0,
	align: 'center'
});
tutorialText.anchor.set(.5, 1);
tutorialText.y = -50;
LK.gui.bottom.addChild(tutorialText);
game.score = 0;
game.obstacleSpeed = 5;
game.obstacleSpeedIncrease = 0.005;
game.checkObstacleCollision = function (obstacles) {
	for (var i = 0; i < obstacles.length; i++) {
		obstacles[i]._move_migrated();
		var dist = Math.sqrt(Math.pow(bird.x - obstacles[i].x, 2) + Math.pow(bird.y - obstacles[i].y, 2));
		if (dist < 280) {
			LK.setScore(game.score);
			LK.getSound('gameOverJingle').play();
			LK.showGameOver();
		}
	}
};
game.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.top.addChild(scoreText);
var scoreText2 = new Text2('0', {
	size: 150,
	fill: '#ffffff',
	font: 'Impact'
});
scoreText2.anchor.set(.5, 0);
scoreText2.x = -4;
scoreText2.y = -5;
LK.gui.top.addChild(scoreText2);
LK.gui.top.addChild(scoreText);
var bird = game.addChild(new Bird());
var leftWall = game.addChild(new Wall());
leftWall.x = 2048;
leftWall.y = 1366;
var rightWall = game.addChild(new Wall());
rightWall.x = 0;
rightWall.y = 1366;
var leftObstacles = [],
	rightObstacles = [];
var obstacleSpawnRandomness = 120;
var obstacleSpawnRandomnessDecrease = 0.025 * (2 / 3);
var obstacleSpawnY = -500;
var leftObstacleSpawnTime = Math.floor(Math.random() * obstacleSpawnRandomness) + obstacleSpawnRandomness;
var rightObstacleSpawnTime = Math.floor(Math.random() * obstacleSpawnRandomness) + obstacleSpawnRandomness;
bird.x = 1700;
bird.y = 1366;
game.isMouseDown = false;
game.down = function (x, y, obj) {
	bird.flap();
	game.isMouseDown = true;
	// Lay an egg at bird's position
	if (!game.eggs) game.eggs = [];
	var egg = game.addChild(new Egg());
	egg.x = bird.x;
	egg.y = bird.y + 80;
	egg.scale.x = 14;
	egg.scale.y = 8;
	game.eggs.push(egg);
};
game.up = function (x, y, obj) {
	game.isMouseDown = false;
};
game.update = function () {
	bird._update_migrated();
	if (game.score > 2) {
		tutorialText.y += 5;
		tutorialTextWhite.y += 5;
	}
	scoreText.setText(game.score);
	scoreText2.setText(game.score);
	game.obstacleSpeed += game.obstacleSpeedIncrease;
	obstacleSpawnRandomness -= obstacleSpawnRandomnessDecrease;
	if (obstacleSpawnRandomness < 20) {
		obstacleSpawnRandomness = 20;
	}
	if (LK.ticks >= leftObstacleSpawnTime) {
		var newObstacle = game.addChildAt(new Obstacle(), 0);
		newObstacle.x = 2048;
		newObstacle.y = obstacleSpawnY;
		leftObstacles.push(newObstacle);
		leftObstacleSpawnTime += Math.floor(Math.random() * obstacleSpawnRandomness) + obstacleSpawnRandomness;
	}
	if (LK.ticks >= rightObstacleSpawnTime) {
		var newObstacle = game.addChildAt(new Obstacle(), 0);
		newObstacle.x = 0;
		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();
		game.score++;
		LK.setScore(game.score);
		LK.getSound('bounce').play();
	}
	for (var i = leftObstacles.length - 1; i >= 0; i--) {
		leftObstacles[i]._move_migrated(game.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_migrated(game.obstacleSpeed);
		if (rightObstacles[i].y > 3232) {
			rightObstacles[i].destroy();
			rightObstacles.splice(i, 1);
		}
	}
	game.checkObstacleCollision(leftObstacles);
	game.checkObstacleCollision(rightObstacles);
	// Update eggs
	if (game.eggs) {
		for (var i = game.eggs.length - 1; i >= 0; i--) {
			if (game.eggs[i] && typeof game.eggs[i].update === "function") {
				game.eggs[i].update();
			}
		}
	}
	if (bird.y < 0 || bird.y > 2732) {
		LK.setScore(game.score);
		LK.getSound('gameOverJingle').play();
		LK.showGameOver();
	}
};

===================================================================
--- original.js
+++ change.js
@@ -6,9 +6,11 @@
 	var birdGraphics = self.attachAsset('bird', {
 		anchorX: 0.5,
 		anchorY: 0.5
 	});
-	self.xSpeed = -10.9375;
+	// Flip the bird horizontally so it faces left initially
+	self.scale.x = -1;
+	self.xSpeed = 10.9375;
 	self.ySpeed = -20;
 	self.gravity = 1;
 	self.lift = -15;
 	self.flap = function () {
@@ -156,21 +158,21 @@
 LK.gui.top.addChild(scoreText2);
 LK.gui.top.addChild(scoreText);
 var bird = game.addChild(new Bird());
 var leftWall = game.addChild(new Wall());
-leftWall.x = 0;
+leftWall.x = 2048;
 leftWall.y = 1366;
 var rightWall = game.addChild(new Wall());
-rightWall.x = 2048;
+rightWall.x = 0;
 rightWall.y = 1366;
 var leftObstacles = [],
 	rightObstacles = [];
 var obstacleSpawnRandomness = 120;
 var obstacleSpawnRandomnessDecrease = 0.025 * (2 / 3);
 var obstacleSpawnY = -500;
 var leftObstacleSpawnTime = Math.floor(Math.random() * obstacleSpawnRandomness) + obstacleSpawnRandomness;
 var rightObstacleSpawnTime = Math.floor(Math.random() * obstacleSpawnRandomness) + obstacleSpawnRandomness;
-bird.x = 1024;
+bird.x = 1700;
 bird.y = 1366;
 game.isMouseDown = false;
 game.down = function (x, y, obj) {
 	bird.flap();
@@ -201,16 +203,16 @@
 		obstacleSpawnRandomness = 20;
 	}
 	if (LK.ticks >= leftObstacleSpawnTime) {
 		var newObstacle = game.addChildAt(new Obstacle(), 0);
-		newObstacle.x = 0;
+		newObstacle.x = 2048;
 		newObstacle.y = obstacleSpawnY;
 		leftObstacles.push(newObstacle);
 		leftObstacleSpawnTime += Math.floor(Math.random() * obstacleSpawnRandomness) + obstacleSpawnRandomness;
 	}
 	if (LK.ticks >= rightObstacleSpawnTime) {
 		var newObstacle = game.addChildAt(new Obstacle(), 0);
-		newObstacle.x = 2048;
+		newObstacle.x = 0;
 		newObstacle.y = -newObstacle.height;
 		rightObstacles.push(newObstacle);
 		rightObstacleSpawnTime += Math.floor(Math.random() * obstacleSpawnRandomness) + obstacleSpawnRandomness;
 	}