Kostogher and Fran Marder are as far as I'm concerned. You can live without Kampen... but it's still good.
Blood of Kingu is Roman Saenko's (Hate Forest/Drudkh fame) side project. Much more similar to Hate Forest than Drudkh, although it will remind you of both. Excellent album, however, I'm not sure why it was re-issused because the original should be pretty easy to find.