Blackguard

[Kshahdoo]

I want this prestige class in the game. I don't think it's hard to implement it, and it'd be an interesting choice, considering the game's plot.

[Procrastinating Gamer]

Sadly, the Blackguard was not released under OGL (the Open Game License that the core parts of DnD 3.5 were released under and the only parts you can use in a purchaseable work without it being copyright infringement) so Paizo doesn't have legal access to it.

Here is the full list of Prestige Classes that are in Pathfinder.[aonprd.com] The ones from the 3.5 DMG (like the Dragon Disciple and Mystic Theuge) are the ones that were published under the OGL and were available for Paizo to use without having to organise a license agreement with Wizards of the Coast.

[Kshahdoo]

Hmm, kinda weird there is no any dark paladin type of prestige.

[solthusx]

Well, there is in fact an Anti-Paladin base class. It requires CE alignment by default but has Archetypes that allow for other evil alignments.

Reference:
https://www.d20pfsrd.com/classes/alternate-classes/antipaladin/

[Procrastinating Gamer]

The closest to that that's in the setting are probably the Hellknights, though they don't tend to have divine abilities (barring the ones who multiclassed into Cleric, at least).

[Kshahdoo]

Originally posted by Shadow88:

The closest to that that's in the setting are probably the Hellknights, though they don't tend to have divine abilities (barring the ones who multiclassed into Cleric, at least).

They aren't evil, though. I mean, they can be, but they aren't by their nature, unlike Blackguard.

[Riftwalker]

as mentioned there is the antipaladin in pathfinder.