So my group has a character who wants to be a hellknight....only problem is I don't know quite what a hellknight is. Any help guys? Would it be a prestige class? Some for of anti paladin? Mabe a LN variant paladin.....any thoughts? Had it ever been officially stated?
I dont believe it is a class, just an organization maybe with some "training" to allow the adherents to pick different feats that imitate devils abilities (like a feat to allow a person to use spiked armor like a barbed devil, or to fight in legions or whatever). I understand most are fighters with some rangers and paladins and blackguards
How would you make a Hellknight?
You take a papa Hellknight and a mama Hellknight....
The Hellknights are an order, and while there will probably be a PrC or even core class for them, you can get by quite well with current stuff.
For your average Hellknight, I suggest martial classes: Fighter works, and of course variant Paladins (of Tyranny), and you can also go with Blackguard, if you want. Even Ranger could work for some of them.
But note that the order isn't just a bunch of guys with big weapons beating enemies into pulp. They also have Signifers - arcane or divine spellcasters of the orders. Divine casters will be mostly clerics, of course (or favoured souls, if you have access to those), and most, if not all of them, worship Asmodeus or some other archdevil.
Arcane spellcasters probably run the gamut, with both wizards and sorcerers being present (though I think that Hellknight bards are unheard of). If you have the proper books, you might also want to consider some warmages and warlocks.