Rimworld with rats. It’s a simple concept, yet a tremendously appealing one. Cute colony sim Ratopia has just left early access after 18 months, and developer Cassel Games has a special Steam sale to celebrate. Boasting an impressive 88% user rating, its adorable art style and clean UI gives its detailed social simulation and intricate systems an immediately eye-catching look, and 1.0 brings a whole swarm of upgrades to the table.

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