Endings
While RimWorld can be played for several hours or indefinitely, the game can come to an end in a few different ways, two of which ends your current game permanently.
For endgame tips, see Advanced Endgame Guide - Ending the game.
Temporary Ending
These endings will not end the game permanently, but instead can go on even when there are no colonist left to control if you chose 'Keep Playing' instead of exiting to main menu. Anytime if the 'wanderer joins' or 'refugee chased' events trigger, you can resume playing.
Colony End
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. If you continue playing, there is very little to do, but time continues to pass and events still trigger.
Ship Launch
If a spaceship is constructed you can load some or all of the colonists into the ship cryptosleep caskets to depart the planet.
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. The credits will list colonists who died to commemorate them.
Journey Offer
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.
Charlon Whitestone friendly AI
Journey destination
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%.
Permanent Ending
These endings will end the game permanently. You can still continue from your last saves if you had saved one.
Planetkiller
If "Planetkiller" is enabled at the scenario, there is a warning timer at the bottom right. Once the timer hits, the entire map will fade to white with the weapon obliterating the rimworld planet, and a message will be shown on your screen to state you didn't survive the impact, only allowing you to return to main menu as it permanently ends your game, regardless whether or not your colonist has escaped.
Archo Nexus (Ideology DLC)
An alternative game ending with the DLC "Ideology", it gives you the progressive quest "The archonexus", which requires you to sacrifice your $350k+ worth of colony and currently allied with said faction for an archo nexus map part. Everything will be gone and shifted to another colony in a new planet, but you can bring up to 5 colonist, 5 animals and 2 relics with you. Upon creation of a new colony, you will need to get a colonist to decipler at one of the nearest archotech structure before you can continue on with the quest.
After the third map fragment is obtained, the location to the archo nexus will be found. While it is guarded by mechanoids, they can be dispatched off quickly and all colonist can be sent over to activate the archo nexus. The game will end permanently upon activation of the nexus, and after exiting the credits screen, you will be greeted back to the main menu.