They're moving much much more to the scream-ey metalcore sound. They pretty much sound like Atreyu at this point. Some of the songs work better than others. Enraged is pretty fun while King of Clubs is pretty bad. This is a guilty pleasure area of mine so I dig it, but others should beware.

Why couldn't have they stuck with Hell Frost's sound

This album is certainly not quite as technical as past endeavors... but I'd say the keyboards and some of the melodies have improved. But yeah, they are treading dangerously close to metalcore now.