Lanbril is one of a number of thief cults. I believe that it hearkens back to the Second Age -- not that it was necessarily an artificial God-Learner cult (more likely a reaction _against_ that), but that it thrived in Theyalan God-Learner areas. Lanbril is known in Pavis, and I would expect Lanbril in Nochet, Handra, etc.
I doubt Lanbril makes much headway in most Orlanthi towns, such as Jonstown or even Boldhome. I think the cult requires a highly-populated urbs which is either non-Orlanthi, or in which the normal Orlanthi social structures have degenerated. The typical Orlanthi mores -- kin-based, warrior-oriented, tribalistic, sub-capitalist, and agricultural -- are rather hostile to an organized thief group, at least to a rural one such as Lanbril hosts. Bandits, murderers of passion, and chicken thiefs are the felons of Orlanthi society.
I doubt it has made its way into the Lunar Empire. The main organized crime network there belongs to Krarsht, which is better-suited for preying upon a highly bureacratic centralized society.
Naturally, most thieves, even where Lanbril is most popular, don't worship the cult, but professionals know about it, use it as a source for contacts, buy its services, etc.
In Pavis, the Lanbril cult no doubt has numerous overlap with the Black Fang organization.
The various odd spells and other tidbits probably are still there, if uncommon. I personally think that Lanbril has a lot of weird specialty stuff -- they're a relict cult, with oddities and tidbits left over from long ago, yet unlike most such cults, Lanbril's members are generally hard-eyed practical criminals, who belong to the cult primarily out of self-interest. It is more of a Tong, than a religion, but not so well-developed and organized as an Earthly Tong. Still, it is a reasonably widespread secret society, and membership has its value.
NOTE: it is probable that a Saint Lanbril is known in Refuge.
Sandy P.
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