They are practicioners in the art of black magic and can turn into Werefalcons at night, in Werefalcon form they are inhumanly agile in the air and are skilled flyers hence why most of them are considered terrorists.
Most of them are known for their bad spelling and grammar and their inability to listen to reason. They will go to any lengths to prove that they are edgy or badass or tough.
Famous examples of Serbian trolls can be found on youtube.
"Must be those Serbians again."
Serbian: BLAH BLAH BLAH, I CANT HEAR YOU!!! WE ROCK!!!! *goes and cries in the corner*