Darka's return were discussed some time ago.
Hawthorne going with that Shadowhaven thing kind of makes it a bit moot. If Darka would start now it would be only Azzal & Massilion and not sure how many nobles would join... Even thought Talerium is a bit boring situation atm. Darkans have been taken as full Talerium members and we have enjoyed our stay... althought war would taste good 
-Jaune
Trust me, I, and plenty of others, would welcome a return of Darka.
