===================================================================
--- original.js
+++ change.js
@@ -1,14 +1,174 @@
-var LevelManager = Container.expand(function () {
+var LevelManager = (function () {
+	var currentLevel = 1;
+	var maxLevel = 16;
+	function getNextLevel() {
+		if (currentLevel < maxLevel) {
+			currentLevel++;
+		}
+		return currentLevel;
+	}
+	function resetLevels() {
+		currentLevel = 1;
+	}
+	return {
+		getNextLevel: getNextLevel,
+		resetLevels: resetLevels,
+		getCurrentLevel: function () {
+			return currentLevel;
+		}
+	};
+})();
+var levelParameters = [{
+	presentSpeedFactor: 2,
+	bounceFactor: 0.6,
+	gravity: 0.1
+}, {
+	presentSpeedFactor: 2.2,
+	bounceFactor: 0.65,
+	gravity: 0.12
+}, {
+	presentSpeedFactor: 3,
+	bounceFactor: 0.8,
+	gravity: 0.2
+}, {
+	presentSpeedFactor: 4,
+	bounceFactor: 0.8,
+	gravity: 0.3
+}, {
+	presentSpeedFactor: 3.5,
+	bounceFactor: 0.8,
+	gravity: 0.2
+}, {
+	presentSpeedFactor: 3.5,
+	bounceFactor: 0.8,
+	gravity: 0.2
+}, {
+	presentSpeedFactor: 3.5,
+	bounceFactor: 0.8,
+	gravity: 0.2
+}, {
+	presentSpeedFactor: 3.5,
+	bounceFactor: 0.8,
+	gravity: 0.2
+}, {
+	presentSpeedFactor: 3.5,
+	bounceFactor: 0.8,
+	gravity: 0.2
+}, {
+	presentSpeedFactor: 3.5,
+	bounceFactor: 0.8,
+	gravity: 0.2
+}, {
+	presentSpeedFactor: 3.5,
+	bounceFactor: 0.8,
+	gravity: 0.2
+}, {
+	presentSpeedFactor: 3.5,
+	bounceFactor: 0.8,
+	gravity: 0.2
+}, {
+	presentSpeedFactor: 3.5,
+	bounceFactor: 0.8,
+	gravity: 0.2
+}, {
+	presentSpeedFactor: 3.5,
+	bounceFactor: 0.8,
+	gravity: 0.2
+}, {
+	presentSpeedFactor: 3.5,
+	bounceFactor: 0.8,
+	gravity: 0.2
+}, {
+	presentSpeedFactor: 3.5,
+	bounceFactor: 0.8,
+	gravity: 0.2
+}];
+var presentTypeDisplay = Container.expand(function () {
 	var self = Container.call(this);
-	self.currentLevel = 3;
-	self.maxLevel = 16;
-	self.advanceLevel = function () {
-		if (self.currentLevel < self.maxLevel) {
-			self.currentLevel++;
+	var level = LevelManager.getCurrentLevel();
+	var presentTypesCount = 2;
+	if (level >= 5 && level <= 8) {
+		presentTypesCount = 4;
+	} else if (level >= 9 && level <= 12) {
+		presentTypesCount = 6;
+	} else if (level >= 13) {
+		presentTypesCount = 8;
+	}
+	var presentTypes = [];
+	for (var i = 0; i < presentTypesCount; i++) {
+		presentTypes.push('presentType' + (i + 1));
+	}
+	self.setRandomPresentTypeIndex = function () {
+		var presentTypeIndex = Math.floor(Math.random() * presentTypesCount);
+		var displayGraphic = self.createAsset(presentTypes[presentTypeIndex], presentTypes[presentTypeIndex] + ' Graphics', 0.5, 0.5);
+		displayGraphic.scale.x = 1.5;
+		displayGraphic.scale.y = 1.5;
+		if (self.children.length > 0) {
+			self.removeChildAt(0);
 		}
+		self.addChild(displayGraphic);
 	};
+	self.setRandomPresentTypeIndex();
+	LK.setInterval(self.setRandomPresentTypeIndex, (Math.random() * (9 - 3) + 3) * 1000);
 });
+var Present = Container.expand(function (type) {
+	var self = Container.call(this);
+	self.applyGravity = function () {
+		var level = LevelManager.getCurrentLevel() - 1;
+		var gravity = levelParameters[level].gravity;
+		self.vy += gravity;
+	};
+	var presentGraphics = self.createAsset(type, type + ' Graphics', .5, .5);
+	self.vx = (Math.random() - 0.5) * 10;
+	self.vy = (Math.random() - 0.5) * 10;
+	self.rotationSpeed = (Math.random() - 0.5) * 0.2;
+	self.interactive = true;
+	self.move = function () {
+		self.applyMovement();
+	};
+	self.applyMovement = function () {
+		var levelIndex = LevelManager.getCurrentLevel() - 1;
+		var level = levelParameters[Math.max(0, Math.min(levelIndex, levelParameters.length - 1))];
+		var presentSpeedFactor = level.presentSpeedFactor;
+		self.x += self.vx * presentSpeedFactor;
+		self.y += self.vy * presentSpeedFactor;
+		self.rotation += self.rotationSpeed;
+		self.applyBounds();
+	};
+	self.applyBounds = function () {
+		var mainContainer = self.parent;
+		if (self.x < 0) {
+			self.x = 0;
+			self.vx = -self.vx;
+		}
+		if (self.x > mainContainer.width - self.width) {
+			self.x = mainContainer.width - self.width;
+			self.vx = -self.vx;
+		}
+		if (self.y < 0) {
+			self.y = 0;
+			self.vy = -self.vy;
+		}
+		if (self.y > mainContainer.height - self.height) {
+			self.y = mainContainer.height - self.height;
+			self.vy = -self.vy;
+		}
+	};
+	self.bounce = function (collisionNormal) {
+		self.applyBounce(collisionNormal);
+	};
+	self.applyBounce = function (collisionNormal) {
+		var level = LevelManager.getCurrentLevel() - 1;
+		var bounceFactor = levelParameters[level].bounceFactor;
+		if (collisionNormal.x !== 0) {
+			self.vx = -self.vx * bounceFactor;
+		}
+		if (collisionNormal.y !== 0) {
+			self.vy = -self.vy * bounceFactor;
+		}
+	};
+});
 var Present = Container.expand(function () {
 	var self = Container.call(this);
 	var presentGraphics = self.createAsset('present', 'Present Graphics', 0.5, 0.5);
 	self.move = function () {
@@ -45,11 +205,12 @@
 	self.y = 3200;
 });
 var Game = Container.expand(function () {
 	var self = Container.call(this);
+	self.presents = [];
 	var mainContainer = new MainContainer();
 	self.addChild(mainContainer);
-	self.levelManager = new LevelManager();
+	self.levelManager = LevelManager;
 	LK.on('tick', function () {
 		mainContainer.children.forEach(function (child) {
 			if (child instanceof Present) {
 				child.move();
@@ -61,13 +222,30 @@
 	var mainContainer = new MainContainer();
 	self.addChild(mainContainer);
 	var santaSack = new SantaSack();
 	self.addChild(santaSack);
-	self.levelManager = new LevelManager();
 	var background = self.createAsset('background', 'Background Image', 0, 0);
 	background.width = 2048;
 	background.height = 2732;
 	self.addChildAt(background, 0);
+	var level = self.levelManager.getCurrentLevel();
+	var presentTypesCount = 2;
+	if (level >= 5 && level <= 8) {
+		presentTypesCount = 4;
+	} else if (level >= 9 && level <= 12) {
+		presentTypesCount = 6;
+	} else if (level >= 13) {
+		presentTypesCount = 8;
+	}
+	for (var i = 0; i < presentTypesCount; i++) {
+		for (var j = 0; j < 5; j++) {
+			var presentType = new Present('presentType' + (i + 1));
+			presentType.x = Math.random() * (mainContainer.width - presentType.width);
+			presentType.y = Math.random() * (mainContainer.height - presentType.height);
+			mainContainer.addChild(presentType);
+			self.balls.push(presentType);
+		}
+	}
 	var snowflakes = [];
 	LK.on('tick', function () {
 		for (var i = 0; i < snowflakes.length; i++) {
 			snowflakes[i].move();
@@ -90,6 +268,16 @@
 			newSnowflake.y = 0;
 			snowflakes.push(newSnowflake);
 			self.addChild(newSnowflake);
 		}
+		for (var i = self.presents.length - 1; i >= 0; i--) {
+			var present = self.presents[i];
+			present.move();
+			if (present.y >= LK.stageContainer.height - present.height) {
+				present.y = LK.stageContainer.height - present.height;
+				present.vy = 0;
+				self.removeChild(present);
+				self.balls.splice(i, 1);
+			}
+		}
 	});
 });