If Minthara was knocked out during the raid in ACT I; having her in the party once recruited will permanently cause her to globally keep dragging Cerys into combat throughout every single ACT II and ACT III encounter, since Cerys is present in both acts.

[Linked Image from bg3.wiki]

*As can be seen as soon as Minthara enters combat, Cerys is immediately dragged into it from the other side of the world. How is anyone supposed to have Minthara in the party like this*