That Space Invaders part completely ruined the game. Slow fire rate, but that's the smallest flaw. At the moment when I hit the last enemy of the wave 10 in that part the game FROZE. And there is nothing I can do about it. But wait! It is said that the game is saving progress! NO WAY! When I reloaded the game it brought me back to the very beginning of the second wave of the museum part... just great... the game is bugged & screwed. Fix this.