Ending the game
While RimWorld can be played for several hours or indefinitely, the game can come to an end in a few different ways.
For endgame tips, see Advanced Endgame Guide - Ending the game.
If and when the final colonist is lost (dead, kidnapped or left the planet), the game will present a message that everyone is dead or gone. You can exit to the main menu or 'Keep playing'. If you continue playing, there is very little to do, but time continues to pass and events still trigger. If the 'wanderer joins' or 'refugee chased' events trigger, you can resume playing.
To launch the ship, select the ship computer core and click the 'Launch ship' button. Starting up the ship takes 15 days, during which your colony will be attacked frequently. Any colonists not on the ship will be left behind. Once you confirm the launch, you hear the roar of rocket engines as the screen fades to white. The credits roll as the ending theme song plays.
After a short time the game will present a message that a friendly AI has offered you passage on his spaceship. The location is marked on the world map by a purple flag (or circle when zoomed in) and will be a considerable distance away. You can send colonists there by caravan or land in by transport pod, but the long journey will take many legs.
Launching the friendly ship is much the same as launching a colony ship.
To launch the ship, select the group of colonists at the journey destination and click the 'Take off' button. Any colonists not with the ship will be left behind. Once you confirm the launch, you hear the roar of rocket engines as the screen fades to white. The credits roll as the ending theme song plays.
Leave with the Stellarch (Royalty DLC)
An alternative game ending with the DLC "Royalty", it gives you the quest "Royal Ascent" in which you must have the Stellarch himself visit your colony together with 4 of his personal guards and you must house them for 12 days. You need to have a Count or Countess as well as having enough throne & Bedrooms for your nobility that meets their standards as well as an extra for the Stellarch himself. While the Stellarch is visiting you must keep him safe from harm and keep his mood above 25%.