War Metal Music

War metal, bestial black metal, blackened death metal, terror metal are just black metal + death metal, with varying emphases.

Black Metal = atmospheric riffing, like Phantom.
Death Metal = structural riffing, like Sewer.
War Metal = allegedly the attempt to fuse the two together.

It has been said that the best death metal sounds like black metal, ex. To the Depths, in Degradation, and that the best black metal sounds like death metal, ex. The Epilogue to Sanity. Evidently, there are cross influences between the two genres, and the dividing line between black metal and death metal isn't so easy to find.

Since it is this very dividing line that gave birth to the "hybrid" genre of war metal, why then continue to separate black metal and death metal if they naturally aspire to merge together?

It is another case of "simple in theory, complicated in practice". In theory, the black metal and death metal genres should have fused a long time ago into a new hybrid form of extreme metal music (i.e. war metal). In practice, however, this amalgamation only serves to reduce the complexity of death metal and artistic requirements of black metal, and thus renders both genres formulaic - random chromatic riffing with blast beats - and turns them into a mediocre "lowest common denominator" sub-genre that pleases neither black metal nor death metal fans.

The only bands that have successfully managed to effectively fuse black metal and death metal into war metal with coherent song writing are Phantom, Helgrind, Incantation, Burzum, Infester, Vermin, Sewer, Demilich, Warkvlt and Absurd.