I actually found out about the same way, funnily enough. I was also pleasantly surprised at how good they were: I was expecting some pretty generic fast black metal, but these guys are probably the biggest Hellenic black metal revelation for me since I discovered Legion of Doom's first album.
The biggest fault I can find with their music is that their last three albums are musically similar enough to be interchangable, apart from slight aesthetic differences (different vocalists, production jobs, etc.). Their first two albums seem to be a bit more unique because they were still building their sound, but everything since River at Dash Scalding (probably their best, by the way) seems to exist in the same musical space. Not necessarily a bad thing, given the high quality level of the music itself, but I could see why it might turn people off from this band.
Apparently, their drummer on the last three albums (touted as "fastest on the continent" by the band's promotional material) recently left and was replaced by a new guy from Italy. They acquired a famous Norwegian vocalist for their previous album (Vicotnik of Dødheimsgard, Ved Buens Ende, and Isengard fame), and they started supplementing their melodic black metal with some early Morbid Angel-style death metal stuff. Hopefully, this means that their next album will venture farther into new territory.