Crusaders of Space 2 takes the classic gameplay and adds a number of modern innovations. One improvement is the ability to fire missiles at enemies. As you shoot down invaders, aliens sometimes drop missiles you can collect. An enemy might also release one of three weapon boosts. The Freeze boost, for example, stops an invader in its tracks and shuts down its weapons. COS2 also allows you to upgrade your ship between levels using points earned during combat. These can be spent on increased firepower or other bonuses. Since you can reclaim points spent on one improvement and apply them elsewhere, you can try out various strategies for beating different parts of the game. By mixing innovation with timeless gameplay, COS2 proves everything old is new again.