i'll preface this noting that I rarely, if ever, dabble into viking beyond Doomsword. I mean, when one band does it the absolute best, everything else is kind of irrelevent.
track 1: I could see where it would be called viking, but it's got a lot of trad/power in it. not to mention a lot of boring. it's one of those situations where you either need to stick to a genre and perfect it or leave the hall.
track 2: about 1:50 in it's got your standard viking breakdown. i don't know what it is about the fast parts, but they don't sound very black metal, despite the similiarity to ITNE. it just sounds "lighter" than bm. viking.
track 3: it's got that fast bm style, but lighter, which is pretty viking-evident. but based on everything, they definitely transcend a single genre, i'd say; or are part of some genre i don't know. folk maybe? there's just too much going on. they sound familiar, too.
track 4: just sounds viking.
also, you really cannot tell me you do not hear the musical shift between black mark and blood fire ice.
further, i was always under the impression drudhk was NSBM. yeah,. yeah. bm is in the title, but NSBM is a defined genre. defined especially by the leaders of the band. which I totally respect after a handful of fags publically ran the third wave of black metal into the fucking ground. (don't get me wrong, some third wavers are good) but it's important because NSBM is all about national proud and sometimes strays far from the darkness and evil that black metal is all the fuck about.
edit: the only reason i'm really pushing this argument is because the genre shift between black mark and bfi is so fucking SO FUCKING legendary.