To get hipsters, you need 12 zero ratings. You don't need to destroy anything. Just restrict all the rooms and make sure that a type of customer has no rooms prioritized for them, so they'll never find a room.
@Bohemico, there are secret arena-like areas in some levels. If there's a challenge referring to a rumble, it's either the arena at the end of the level or one of the secret ones.
It's a very good game overall, but there are a places where it can improve. Since we can't move around, cover should always be an option. I think it would stop some parts of the game being frustrating.
I'll give this a 5/5, not because you're my friend, but because the game is good. You should think of either recharging explosions each level or else making the damage upgrade cheaper, since later levels exhaust your supply of explosions too quickly.
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