looks like we have 1 diplomatic rogue(pling), 1 trap-seeker rogue(matt), 1 archer [with possibly a level in ranger](tas), 1 wizard (lewwyn), 1 monk (com), 1 cleric (brick).
So ... no survival skill? I see Pling has Knowledge Nature and Knowledge local, which is good. If she spends some knowledge on Linguistics and gets some of the local languages (like Damaran, Dwarven, Gnome ... possibly something else), she could be our best possible diplomat. I wonder if there is another nearby local language. If not, Draconic and Giant would be resonably good picks I think (or possibly undercommon if we 'travel too deep').
Due to my backstory, I'll have a high likelihood of knowing Abyssal, (assuming I have enough skill points for at least 1 linguistics slot). The utility of that may or may not be quite limited ... depending on if there are any (ancient?) Abyssal ruins nearby (underneath the glacier?)
Speaking of ancient ruins, is there an anciente language of Faerun? I know Avistan is the ancient language of planet Golarion. So, due to connectiveness of the planes, its POSSIBLE its also the ancient language of Faerun/Forgotten Realms, but not necessarily the case.
Knowing Suparna would automatically give a person the ability to read ancient (and not so ancient) hieroglyphics ... but at the same time, one would have to know that their version of the language wouldn't have the supernatural abilities that it has when the gods speak it. Still ... the ability to read heiroglyphics might prove useful. Wouldn't it be more useful in the south of Faerun though? Hard to say imho, who knows what language the people of the ruins used to speak.
I'd suspect the FR lore has more ancient languages than just planar (abyssal,celestial,infernal,supurnal), and ancient (avistan?, draconic)
Especially if Local languages are enabled, there could be literally hundreds of ancient dialects to choose from, each with a similar linguistic tree to either one of the existing current or existing ancient languages.
either way, clearly current languages are more important from a diplomatic perspective ... but ancient languages are so cool
Btw, looks like Supernal/Suparna isn't perhaps takeable as a linguistics based language (at least it doesn't seem that way. Unfortunate, would be nice to read hieroglyphics
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... but then again, no guarantee there are any nearby)