The Four Winds
Greater Power God of the Dead
Kelemvor is the newest god to join the Forgotten Realms universe. He was a human fighter that traveled with a thief named Cyric (God of Strife), a magic-user named Midnight (Goddess of Magic), and a cleric named Adon (First priest of Mystra). During the Time of Troubles he was responsible along with the others for recovering the Tablets of Fate that were somehow stolen from Everwatch. He was betrayed and murdered by Cyric and found ten years later where he overthrew the god of the dead to take his place and drive him insane. He rekindled his love interest with Midnight, who is now Mystra, goddess of magic. However two years later during the trial of the god Cyric the connection the two felt as mortals was extinguished and Cyric regained his sanity.
Kelmvor is just the latest in a long line of death gods. First was Jurgel, then Myrkul, then Cyric, and now him. How long he will hold the position is anyones guess. Jurgel was the original death god and held it for eons until relinquishing it due to boredom, then Myrkul who held it for millennium till killed in Waterdeep during the Time of Troubles, Cyric held it a paltry years until Kelmvor lead a mutiny in Hades to overthrow him.
If you want to read up on the events outlined above I would highly recommend the books Shadowdale, Tantras, and Waterdeep.
As far as specialty priest go:
They pray for spells at midnight rather then dusk or dawn light most clerics.
Normal weapons for clerics + proficient in Longswords (kelmvors weapon of choice as a mortal) and scythes (all death gods kind of do this)
May take feats normally reserved for fighters only
Constantly under a Negative Energy Protection spell. If ever dispelled then praying at midnight restores it.
Can cast arcane necromantic wizard spells, though they count as being one level higher (chill touch is a 2nd level cleric spell for you, etc)
Can Turn AND Rebuke undead, you dont have to just choose once, doesnt matter if good or evil.
Can cast Disrupt Undead at will as a standard action, 1d6 no save
1/day may cast a Improved Disrupt Undead 1d6 per level no save
+ 2 save vs necromantic effects, +3 at 5th level, +4 at 10th, +5 at 15th, immune at 20th.