The game has a top-down, two-dimensional view. As the game progresses events become progressively harder and the player can unlock more advanced technology through research.

Much of the difficulty as well as the critical acclaim for the game come from its unpredictability, through randomly generated events, and its extensively designed and customizable world. The objective of the game is to ensure the survival of a colony of people, fighting against various environmental and/or internal events. With the Ideology DLC the ArchoNexus ending is made available, which involves selling your colony for part of a map to the ArchoNexus, a massive AI-controlled computer capable of controlling the entire planet. With the Royalty DLC, the game can also end by hosting the High Stellarch, leader of one of the factions that inhabit the Rim, and leaving the colony with them. The game can end when at least one character has escaped the planet on a spaceship, or when they are all dead. Said colonists might also contain negative traits such as being pyromaniacs or psychopaths. Characters can be rescued after crash-landing on the player map, they can wander in, or they can be captured after a raid. As time goes on, more characters will join the colony. The characters have a randomly generated set of traits which affect how they can contribute to the colony, the decisions they make, and how their existence affects the other characters. The player characters (referred to as 'pawns' in game documentation) are stranded on a procedurally generated planet located in the frontiers of known space (a 'rim world'). The game has a small variety of scenarios to choose from, although the core gameplay is the same.

Rimworld alpha 12