diff --git a/src/game/mouse/space_invaders/alien.js b/src/game/mouse/space_invaders/alien.js
index 55f5a38..2cd3b7d 100644
--- a/src/game/mouse/space_invaders/alien.js
+++ b/src/game/mouse/space_invaders/alien.js
@@ -83,10 +83,10 @@ class Alien extends Phaser.Sprite {
 
 	goOnstage() {
 		// set random position
-		const SPAWN_BOX_LEFT		= 50;
-		const SPAWN_BOX_WIDTH		= game.world.width - 100;
-		const SPAWN_BOX_TOP		= 250;
-		const SPAWN_BOX_HEIGHT	= game.world.height - 340;
+		const SPAWN_BOX_LEFT		= 80;
+		const SPAWN_BOX_WIDTH		= game.world.width - 160;
+		const SPAWN_BOX_TOP		= 280;
+		const SPAWN_BOX_HEIGHT	= game.world.height - 400;
 
 		this.x = SPAWN_BOX_LEFT + Math.random() * SPAWN_BOX_WIDTH;
 		this.y = SPAWN_BOX_TOP + Math.random() * SPAWN_BOX_HEIGHT;
diff --git a/src/game/mouse/space_invaders/game.js b/src/game/mouse/space_invaders/game.js
index a81b915..1133239 100644
--- a/src/game/mouse/space_invaders/game.js
+++ b/src/game/mouse/space_invaders/game.js
@@ -21,11 +21,17 @@ class Game {
 
 
 		// contents
-		let alien = new Alien(100, 150, this.onAlienFired, this.onAlienEscaped);
-		alien.goWaitingRoom();
+		this.alienGroup = game.add.group();
+		this.alienGroup.inputEnableChildren = true;
+		for(let i = 0; i < 10; i++) {
+			let alien = new Alien(150 + 80 * i, 150, this.onAlienFired, this.onAlienFired);
+			alien.goWaitingRoom();
+			alien.setActive(false);
+			this.alienGroup.add(alien);
+		}
 
 		// activate first alien
-		alien.setActive(true);
+		// this.alienGroup[0].setActive(true);
 
 
 		// bottom