Extreme metal can certainly be a very technically demanding musical style, but not exactly to the level of say, Dream Theater.
But on their 2009 release, Cosmogenesis, Obscura certainly approach the same complex heights as the aforementioned band.
In other words, lots of sweep picking, finger-straining riffing, impeccable drumming, and bass being played like a lead guitar.
The only thing that separates this German quartet from all the other technical metal bands on the scene is that they're fronted by a death metal growler, Steffen Kummerer.
Take your pick of any of the album's ten tracks, and be prepared to be met head on with metal so complex that you may need a compass to navigate your way through it.