I don't remember the thread where there was speculation about Karlach and the nature of her presence on the Nautiloid. I talked with her and she is a stowaway, not part of a boarding party.
And she is being hunted as "I'm good at killing demons. And I like it!" leading to "devils don't like to lose their assets."
Interesting feat - Martial prodigy - gets Light and Medium Armour proficiencies, plus those in Short, Longs and Great swords.
In unrelatred news I found a bauble which allows one to cast Guidance. Hence no need for Shadowheart as she can be replaced.
The discussion you're thinking of is in
this thread. And yes, she has intentionally used the ship as a route out of the hells, but to me that doesn't necessarily entail that she wasn't originally sent to it as part of the boarding party we encounter in the prologue but rather than fighting the illithids as she was meant to she separated herself from her companions with the aim of leaving Avernus along with the nautiloid
And yes, there is indeed an amulet that lets you cast Guidance. Personally, I disapprove, and think this devalues having Clerics and Druids with the spell in our parties. At the very least, I think it should be limited to just a few uses per rest. But I know others disagree and anyway I shouldn't take us down that rabbit hole. Apologies!
