Karlach is a companion and an origin character in Baldur’s Gate 3. She has a unique questline of her own, which gives you access to her multiple unique endings. A lot of Karlach’s endings in BG3 are tied to how you progress her companion quest.
Karlach is a Tiefling Barbarian that you can recruit during Act 1. She suffers from a unique condition called Infernal Engine. Her heart has been replaced with a ticking time bomb that only you can help to save.
In this guide, we will guide you through all Karlach’s endings in BG3 and tell you the exact steps you can take to achieve them. As it is not possible to get all the endings in one playthrough, you can stick with the one you want most and read up on the rest to see which ones you missed.
Kill or Abandon Karlach
Once you reach the Druid Grove and recruit Wyll, he will ask you to hunt a demon with him. Mizora asks him to kill Karlach.
Once you find Karlach, she will tell you that she is not a devil. However, if you still decide to kill her for Wyll, her story will come to an end at that point. You can also leave Karlach, never to interact with her again.
This is one of the bad endings you can get for Karlach in BG3.
Send Karlach to Avernus
If you complete Karlach’s companion quest, Our Fiery Friend, by upgrading her infernal engine twice, you will get a chance to send her to Avernus at the end of Act 3.
Suppose you also manage to complete Wyll’s companion quest, Blade of the Frontiers, and turn him into the Blade of Avernus. In that case, he will be willing to accompany Karlach into Avernus and protect hr from Zariel.
If you romance Karlach, you can also join her to go into Avernus with her. You will once again meet with all of your companions six months later, and at Withers’ party in the epilogue, and share your adventures from hell.
Upon romancing Wyll and turning him to the Blade of Avernus, you can go with Wyll and Karlach to Avernus after defeating the Netherbrain at the end of Act 3. The events will play out the same, and you will once more meet during the epilogue.
The endings mentioned above are all considered the best endings for Karlach, as this will allow her to get rid of her condition once and for all.
Honor Karlach’s Wish
Upon completing Act 3 by defeating the Netherbrain, Karlach will ask your permission to let her burn out by using her infernal engine. This will result in two different endings depending on how much you have progressed in her companion quest.
If you complete Karlach’s companion quest by upgrading her infernal engine twice, she will burn out in front of the whole party, leading to an emotional goodbye.
However, if you didn’t upgrade Karlach’s infernal engine, she will burn out in the background without anyone noticing.
Despite honoring Karlach’s wishes, these are considered bad endings for Karlach, as this is a sad way to go for our resident barbarian.
Becoming an Illithid
At the end of Act 3, you must turn yourself or a party member into a Minflayer to control the Netherbrain. If you choose Karlach, she will perform her duty marvelously, and this will also destroy her infernal engine without hurting her.
However, she will continue to be a Mindflayer for the rest of her life. This is a mix ending for Karlach as it has a bittersweet outcome.
You can also choose to betray Karlach after turning her into a Mindflayer. This will result in you stabbing Karlach over and over again. This will kill her on the spot, ending her story abruptly. This is also one of the worst endings for her.
Becoming the Absolute Yourself
If you decide to kill the Emperor or the Mindflayer from your party without turning Karlach into one, this will allow you to control the Netherbrain and become the tyrant in the process.
Karlach will become obsessed with you and follow your bidding into wreaking havoc upon the innocent denizens of Baldur’s Gate. This is a bad ending for Karlach, as she will be robbed of her free will by you.
Turn into a Tyrant
If you are playing with Karlach as an origin character, you can betray the Emperor or the Mindflayer from your party near the end of Act 3. This will allow Karlach to dominate the Elder Brain and become the tyrant herself.
She can access multiple bad endings at this point, once passing a constitution check. These involve.
- Will all of Baldur’s Gate to perish.
- Command the citizens of Baldur’s Gate to kill each other.
- Conquer the world with the army of the absolute.
- Brainwash the citizens of Baldur’s Gate to work for you. They will rebuild the city unaware of their fates.
However, she will also get an additional option for the fifth bad ending. Karlach will open the gates of Avernus and unleash hell upon the residents of Baldur’s Gate.
At this point, she will also rip out her infernal engine and start killing everyone indiscriminately. These are all evil endings for Karlach, including the one where you turn into a Mindflayer for the absolute.
