Groovydude2

Brought the weapon that killed Rayse, indirectly led Navani to discovering the method to create anti-light, trained Adolin who saved Azir from being controlled by Retribution, helped guide Kaladin who is the only new Herald in Roshar's history. His current visit sounds very impactful and I'm most likely forgetting more.

I figured it was the Mink based on earlier scenes of him hiding with Lift to eavesdrop on meetings

AH! That does completely destroy this theory. RIP. The WOB giveth and the WOB taketh away... I'll have to keep that in mind for my current and future re-reads!

Thanks for the welcome! Lurked for a while, made an account to post. This all makes sense, but I still have my suspicions. Hundreds of years isn't much compared to the tens of thousands of years (most likely longer) they've already been on Roshar, and it seems likely a horde on Scadrial is not directly coming from Roshar but from their original home planet. Additionally, the highlighted quote implies that on Scadrial their evolution would need to be different and might end up having fewer noticeable "breaks" in the skin since they wouldn't be as crablike in appearance to begin with.

Re-reading Well of Ascension and Noorden was just introduced, an Obligator seems like an ideal candidate for a Dysian Aimian. Not only do they have the telltale tattoos, but Noorden specifically is mentioned to be unlike most of the other Obligators, focuses on his research (gathering information on this planet for the horde at large?), he works alone, and is in a position of power in the Lord Ruler's government. Any thoughts?