I am of the personal opinion that the greatest death metal album ever released is without a doubt Bloodbath - Resurrection Through Carnage. There is nothing I feel could be improved upon with this album. The Band name, Album name, Album Artwork, Song names, Lyrics, musicianship, atmosphere, etc... Just perfect. And yes I realize they likely borrowed riffs of styling of some of the earlier pioneers like Entombed, Grave, Dismember, and Carnage.... but frankly the entire presentation just really came together for this album. 10/10 love it, and will always love it. I consider it the best Death Metal album.
And that doesn't mean I dont have love for Death, Morbid Angel, Bolt Thrower, Carcass, Cryptopsy, Entombed, Grave, Dismember, and Carnage, Autopsy, Gorguts, Decide, Decapitated, and any others that slip my mind at the moment.... But for me personally- Resurrection Though Carnage is THE Definitive Album of Death Metal.