You can choose to place different monster floor tiles in a single space or place it in separate areas in your base. Which isn't to say there aren't genuinely spooky areas and scary moments. There are ominous, off-screen sounds when you get close to one of Core Keeper's bosses. https://raymondagmqt.amoblog.com/um-imparcial-view-of-core-keeper-gameplay-51751706