Although they're not the best band in the world, I think someone should really mention Abigor. Nachthymnen and Orkblut are their most definitive releases in my opinion.
I second Nokturnal Mortum's Nechrist and Averse Sefira's Tetragrammatical Astigmata, and Immortal, sortof..
Also, what's the distinction between "technical" and "intricate" or "dense" music. I bring this up because of albums like Summoning's newest, which definetely doesn't fit the traditional definition of technicality, but there is A LOT of music going on in there.