over all it's really good, I don't know which genre you prefer the most, because you show great capability with all of them here (death, melodeath, black, etc.). I think you could excel at any you choose.
1. Slaves to our Race
bass is a little overbearing, and those first vocals really should be switched out for the death ones that follow. The dual vox on the hook is nice.
2. Yesterday
odd intro (I'd cut that out). bring out the lead and rhythm a little more and the production would be great. Something about the vocals don't fit, I dunno if it's the tone or the volume or just the lack of clarity cos of the mic, but it just doesn't quite fit right to me. at 2:07 it would be nice if the high vox there droned on a bit fading where the deep vocals begin in the verse again. same production trick might work nice on the chorus The lead on the clean guitar is too loud for the rhythm I think (rhythm needs to be brought up as loud as the drums and lead), and I think a more natural ending would be more effective.
3. Gnawing on Grandma's Clam
nicely produced. not my kinda thing though. (the rhythm guitar about 30seconds in actually reminds me of a song from Slipknot's first album)
4. Screwing Dead Bitches
well put together, but nothing special to me (though I like the change up at 1:17, it would be nice if it progressed to a new riff after that). (Death doesn't impress me easily). nice vox too.
5. Holocaust of Souls
This reminds me so much of some BM song I wish I could rememer what it was (could be by Carpathian Forest). I think the lead at the start, and the second riff need a little work, something in the melody sounds slightly off.
6. Freezing Fog Moon
bass is a little poorly mixed/EQed here, but if you sort that bass EQ and bring up the guitars it would be a really nice track.
7. End
would be nicer with the guitar at the front and the atmospheric noises in the background rather than so loud. (and none of that left/right fading), and instead of the 'power down' sound at the end just let the last note ring, hammer it, and fade out, do sumn nice to end it off. it's a very nice little solo, just needs to be produced right.
8. Human Massacre
a different synth at the start might work better, the loop cycle changing speed with the pitch seems a little odd. That 2:00 section is cool, reminds me a little of Alice in Chains. it would be cool if you brought the pitch all the way down at about 2:14 a la 3:55 into 'Vader - Freezing Moon'. I like the melody on the hook but it would be good if the chorus had more concept, something catchy rather than the same words repeated.