/**** 
* Classes
****/
var Explosion = Container.expand(function () {
	var self = Container.call(this);
	var explosionGraphics = self.attachAsset('explosion', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	self.lifetime = 120; // 2 seconds at 60FPS
	self.tick = function () {
		self.lifetime--;
		if (self.lifetime <= 0) {
			self.destroy();
		}
	};
});
var Star = Container.expand(function () {
	var self = Container.call(this);
	var starGraphics = self.attachAsset('star', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	self.speed = Math.random() * 2 + 1;
	self.alpha = self.speed / 3;
	self.move = function () {
		self.y += self.speed;
		if (self.y > 2732 + self.height / 2) {
			self.y = -self.height / 2;
		}
	};
});
var Hero = Container.expand(function () {
	var self = Container.call(this);
	var heroGraphics = self.attachAsset('hero', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	self.speed = 20;
	self.move = function (x, y) {
		var dx = x - self.x;
		var dy = y - self.y;
		var angle = Math.atan2(dy, dx);
		self.x += Math.cos(angle) * self.speed;
		self.y += Math.sin(angle) * self.speed;
	};
	self.shoot = function () {
		var bullet = new HeroBullet();
		bullet.x = self.x;
		bullet.y = self.y - self.height / 2;
		game.addChild(bullet);
		return bullet;
	};
});
var Enemy = Container.expand(function () {
	var self = Container.call(this);
	var enemyGraphics = self.attachAsset('enemy', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	self.speed = 2;
	self.direction = Math.random() > 0.5 ? 1 : -1;
	self.move = function () {
		var multiplier = getSpeedMultiplier(score);
		self.y += self.speed * multiplier;
		if (LK.ticks % 60 == 0) {
			self.direction = Math.random() > 0.5 ? 1 : -1;
			self.speed = Math.random() * 3 + 2;
		}
		self.x += self.speed * self.direction;
		if (self.x < 0) {
			self.x = 0;
		}
		if (self.x > 2048) {
			self.x = 2048;
		}
		if (self.y > 2732 + self.height / 2) {
			self.destroy();
		}
	};
	self.shoot = function () {
		var bullet = new EnemyBullet();
		bullet.x = self.x;
		bullet.y = self.y + self.height / 2;
		game.addChild(bullet);
		return bullet;
	};
});
var HeroBullet = Container.expand(function () {
	var self = Container.call(this);
	var bulletGraphics = self.attachAsset('heroBullet', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	self.speed = -10;
	self.move = function () {
		self.y += self.speed;
		if (self.y < -self.height / 2) {
			self.destroy();
		}
	};
});
var EnemyBullet = Container.expand(function () {
	var self = Container.call(this);
	var bulletGraphics = self.attachAsset('enemyBullet', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	self.speed = 10;
	self.move = function () {
		var multiplier = getSpeedMultiplier(score);
		self.y += self.speed * multiplier;
		if (self.y > 2732 + self.height / 2) {
			self.destroy();
		}
	};
});

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

/**** 
* Game Code
****/
function getSpeedMultiplier(score) {
	return 1 + score / 100; // As an example, increase speed by 1% for every 100 points scored
}
var stars = [];
for (var i = 0; i < 40; i++) {
	var star = new Star();
	star.x = Math.random() * 2048;
	star.y = Math.random() * 2732;
	stars.push(star);
	game.addChild(star);
}
var hero = game.addChild(new Hero());
hero.x = 2048 / 2;
hero.y = 2732 - 100;
var enemies = [];
var heroBullets = [];
var explosions = [];
var enemyBullets = [];
var score = 0;
var scoreTxt = new Text2(score.toString(), {
	size: 150,
	fill: "#ffffff"
});
scoreTxt.anchor.set(0.5, 0);
LK.gui.top.addChild(scoreTxt);
var targetPos = {
	x: hero.x,
	y: hero.y
};
game.on('down', function (obj) {
	targetPos = obj.event.getLocalPosition(game);
});
game.on('move', function (obj) {
	targetPos = obj.event.getLocalPosition(game);
});
LK.on('tick', function () {
	for (var i = 0; i < stars.length; i++) {
		stars[i].move();
	}
	hero.move(targetPos.x, targetPos.y);
	// Move hero bullets
	for (var i = heroBullets.length - 1; i >= 0; i--) {
		heroBullets[i].move();
		if (heroBullets[i].y < 0) {
			heroBullets[i].destroy();
			heroBullets.splice(i, 1);
		}
	}
	// Move enemies bullets
	for (var i = enemyBullets.length - 1; i >= 0; i--) {
		enemyBullets[i].move();
		if (enemyBullets[i].y < 0) {
			enemyBullets[i].destroy();
			enemyBullets.splice(i, 1);
		}
	}
	// Move enemies and make them shoot
	for (var j = enemies.length - 1; j >= 0; j--) {
		enemies[j].move();
		var fireRate = 30;
		if (LK.ticks % fireRate == 0) {
			enemyBullets.push(enemies[j].shoot());
		}
		if (enemies[j].y > 2732) {
			var explosion = new Explosion();
			explosion.x = enemies[j].x;
			explosion.y = enemies[j].y;
			game.addChild(explosion);
			enemies[j].destroy();
			enemies.splice(j, 1);
		}
	}
	// Check for collisions
	for (var k = heroBullets.length - 1; k >= 0; k--) {
		for (var l = enemies.length - 1; l >= 0; l--) {
			if (heroBullets[k].intersects(enemies[l])) {
				var explosion = new Explosion();
				explosion.x = enemies[l].x;
				explosion.y = enemies[l].y;
				game.addChild(explosion);
				heroBullets[k].destroy();
				heroBullets.splice(k, 1);
				enemies[l].destroy();
				enemies.splice(l, 1);
				score += 10;
				scoreTxt.setText(score.toString());
				break;
			}
		}
	}
	// Check if hero is hit by enemy bullet or enemy
	for (var m = enemyBullets.length - 1; m >= 0; m--) {
		if (hero.intersects(enemyBullets[m])) {
			LK.effects.flashScreen(0xff0000, 1000);
			LK.showGameOver();
		}
	}
	for (var n = enemies.length - 1; n >= 0; n--) {
		if (hero.intersects(enemies[n])) {
			LK.effects.flashScreen(0xff0000, 1000);
			LK.showGameOver();
		}
	}
	// Spawn enemies
	if (LK.ticks % 120 == 0) {
		var enemy = new Enemy();
		enemy.x = Math.random() * (2048 - enemy.width) + enemy.width / 2;
		enemy.y = -enemy.height / 2;
		enemy.speed = Math.random() * 3 + 2; // Set random speed for each enemy
		enemies.push(enemy);
		game.addChild(enemy);
	}
	// Update explosions
	for (var i = explosions.length - 1; i >= 0; i--) {
		explosions[i].tick();
		if (explosions[i].lifetime <= 0) {
			explosions.splice(i, 1);
		}
	}
	// Hero shoot
	if (LK.ticks % 80 == 0) {
		heroBullets.push(hero.shoot());
	}
});
var scoreIncrementTimer = LK.setInterval(function () {
	score += 1;
	scoreTxt.setText(score.toString());
}, 1000);

===================================================================
--- original.js
+++ change.js
@@ -1,7 +1,21 @@
 /**** 
 * Classes
 ****/
+var Explosion = Container.expand(function () {
+	var self = Container.call(this);
+	var explosionGraphics = self.attachAsset('explosion', {
+		anchorX: 0.5,
+		anchorY: 0.5
+	});
+	self.lifetime = 120; // 2 seconds at 60FPS
+	self.tick = function () {
+		self.lifetime--;
+		if (self.lifetime <= 0) {
+			self.destroy();
+		}
+	};
+});
 var Star = Container.expand(function () {
 	var self = Container.call(this);
 	var starGraphics = self.attachAsset('star', {
 		anchorX: 0.5,
@@ -127,8 +141,9 @@
 hero.x = 2048 / 2;
 hero.y = 2732 - 100;
 var enemies = [];
 var heroBullets = [];
+var explosions = [];
 var enemyBullets = [];
 var score = 0;
 var scoreTxt = new Text2(score.toString(), {
 	size: 150,
@@ -169,20 +184,29 @@
 	}
 	// Move enemies and make them shoot
 	for (var j = enemies.length - 1; j >= 0; j--) {
 		enemies[j].move();
-		if (LK.ticks % 60 == 0) {
+		var fireRate = 30;
+		if (LK.ticks % fireRate == 0) {
 			enemyBullets.push(enemies[j].shoot());
 		}
 		if (enemies[j].y > 2732) {
+			var explosion = new Explosion();
+			explosion.x = enemies[j].x;
+			explosion.y = enemies[j].y;
+			game.addChild(explosion);
 			enemies[j].destroy();
 			enemies.splice(j, 1);
 		}
 	}
 	// Check for collisions
 	for (var k = heroBullets.length - 1; k >= 0; k--) {
 		for (var l = enemies.length - 1; l >= 0; l--) {
 			if (heroBullets[k].intersects(enemies[l])) {
+				var explosion = new Explosion();
+				explosion.x = enemies[l].x;
+				explosion.y = enemies[l].y;
+				game.addChild(explosion);
 				heroBullets[k].destroy();
 				heroBullets.splice(k, 1);
 				enemies[l].destroy();
 				enemies.splice(l, 1);
@@ -213,8 +237,15 @@
 		enemy.speed = Math.random() * 3 + 2; // Set random speed for each enemy
 		enemies.push(enemy);
 		game.addChild(enemy);
 	}
+	// Update explosions
+	for (var i = explosions.length - 1; i >= 0; i--) {
+		explosions[i].tick();
+		if (explosions[i].lifetime <= 0) {
+			explosions.splice(i, 1);
+		}
+	}
 	// Hero shoot
 	if (LK.ticks % 80 == 0) {
 		heroBullets.push(hero.shoot());
 	}