There's seriously not an Immolation thread? This must be fixed post-haste. They've been around since 1986 (originally called Rigor Mortis for the first couple years), released their first full-length in 1991, and have released 8 very solid albums total. They're the oldest of the "big three" of the NYC death metal scene, the other two being Suffocation and Incantation.

I should note that, particularly on their old material, they have a lot of anti-religious lyrics. They've backed off on that more recently, though traces can still be found.

As of this year, musically, they've still got it: "IT"