There are about 150,000-200,000 Vadeli in Glorantha, most in the Vadeli Islands or Pamaltela. That’s roughly the same number as Brithini in Arolanit and Sog City.
Although they are descended from Malkion, the Vadeli are antinomian and knowingly transgress against the laws that bind other Malkioni. Despite this (or perhaps because of this) they are immortal and unaging.
Almost all Vadeli encountered in the mundane world belong to the Brown Vadeli, mostly sailors and traders. A few unfortunates have encountered Red Vadeli, the warrior caste.
For whatever reason, I tend to associate the Vadeli with the Deva of Robert Asprin’s Myth Adventures and figure that Phil Foglio could have done one heck of a comic series about the Vadeli.
Given that the Brown and Red Vadeli look different (the Red Vadeli have red skin after all!), we might actually be dealing with different types entities all classified as “Vadeli” and these might be more like different “castes” in an ant community than the castes we see with mundane Malkioni.
The Vadeli antinomianism does lead to immortality, which is pretty cool.