I had always thought the Scarlets are cool from a lore perspective, they just seem simply impossible to pull off on an IC basis, unless you roamed around SM and parts of the plaguelands, but with Legion they are practically destroyed.
Though I saw a GM chat on the subject hinting it is not known if they completely destroyed down to the last man, they appear impossible to RP as. Perhaps as routed Scarlet crusader, fleeing from The Ebon’s, but past that? Hmph. If it was cata, it might have some limited legs in it., but without something substantiate from blizzard they are all but destroyed.
Apparently a GM response on a question
Thank you for your patience! Sorry about the wait, our office equipment is goblin made so explosions do happen!
The Scarlet Crusade suffered badly at the hands of the Knights of the Ebon Blade, in their quest to resurrect Sally Whitemane. While they did declare that they would not leave until every last crusader had been killed and every banner burned, it’s not clear at this moment how far they succeeded. There have been a few sightings of Scarlet Crusade members around the world, but it’s not clear if these are the last remnants of a dying faction or the seeds of a revival. Only time will tell!
What is the state of the Scarlet Crusade? - #10 by Dorlas-magtheridon