Karlach, the Tiefling Barbarian, is one of the best characters in Baldur’s Gate 3. Her character has an infernal engine burning in her chest, which was placed there by Zariel, the Archdemon. By upgrading her infernal engine twice and completing Karlach’s quest, the player will gain access to various options in the ending. However, if you’re still unsure about what to make and are wondering whether or not to let Karlach become a Mind Flayer in Baldur’s Gate 3, here’s everything you need to know before you can accept or reject this selfless offer.

Towards the end, you will be given the option to become a Mind Flayer to control the Netherbrain. However, Karlach will intervene and let you know that she wants to be the one to turn into a Mind Flayer, as she has nothing left to lose. The decision here is yours. You can either let her become a Mind Flayer or become one yourself. However, we recommend not letting Karlach become a Mind Flayer.

This is because she will not be the same once she transforms. She will not feel like she is dying anymore and she will also survive once she destroys the Netherbrain. However, Karlach can also die after defeating the Netherbrain. The possibilities in this situation will depend entirely on the choices you make. If you choose to let her turn into a Mind Flayer, you will also be given the option to betray her, control the Netherbrain, and become the Absolute.

If you want to save Karlach, the best option is to have her return to Avernus with Wyll or the player instead of transforming her into an Illithid. If you don't choose this, the flames of her infernal engine will consume her and she will die.