Do you mean in terms of flavor or in terms of mechanics?
Mechanically, I would just rule that everything that affects fiends affects celestials and everything that affects celestials affects fiends (including the base paladin abilities). If you felt like it made sense, you could swap radiant damage for necrotic damage but I would instead just reflavor the evil radiant energy as something fitting the character ("unholy" light in dark shades of purple and red and green). The parts of the paladin that affect undead might seem out of place but it could make sense if you see it as power over undead rather than power against undead.
Thematically, an evil Oath of Devotion paladin might not see themselves as "bad"...just happening to side with Hell and Devils and a Church that is evil. You could have an oath similar to the Devotion oath but twisted in some way.
One idea that you could try is to take the tenets of the code to the extreme. The computer game Ultima V does this with the Virtues to make an "evil" version of the world's "religion". For example, Compassion becomes less about giving to others and instead is "Thou shalt help those in need, or thou shalt suffer the same need." (https://ultima.fandom.com/wiki/Eight_Virtues if you are interested in seeing the other seven virtues) So basically, as an evil Devotion Paladin, you might punish those who don't help others or give to charity or speak falsehoods or act cowardly with harsh punishments because how else are people going to learn how to be part of society?
...and other people are probably going to say just do Oathbreaker Paladin but that's not what you asked...
Do you mean in terms of flavor or in terms of mechanics?
Mechanically, I would just rule that everything that affects fiends affects celestials and everything that affects celestials affects fiends (including the base paladin abilities). If you felt like it made sense, you could swap radiant damage for necrotic damage but I would instead just reflavor the evil radiant energy as something fitting the character ("unholy" light in dark shades of purple and red and green). The parts of the paladin that affect undead might seem out of place but it could make sense if you see it as power over undead rather than power against undead.
Thematically, an evil Oath of Devotion paladin might not see themselves as "bad"...just happening to side with Hell and Devils and a Church that is evil. You could have an oath similar to the Devotion oath but twisted in some way.
One idea that you could try is to take the tenets of the code to the extreme. The computer game Ultima V does this with the Virtues to make an "evil" version of the world's "religion". For example, Compassion becomes less about giving to others and instead is "Thou shalt help those in need, or thou shalt suffer the same need." (https://ultima.fandom.com/wiki/Eight_Virtues if you are interested in seeing the other seven virtues) So basically, as an evil Devotion Paladin, you might punish those who don't help others or give to charity or speak falsehoods or act cowardly with harsh punishments because how else are people going to learn how to be part of society?
...and other people are probably going to say just do Oathbreaker Paladin but that's not what you asked...
Let me expand a little bit, I apologize for not being very clear. I have a character who is lawful enough that they won't break their oath, but their faith in the cause of good has been shaken to the core. So they had already sworn this Sacred Oath before this path was kind of dropped on them. So I was really looking for advise of how they could keep the oath and still show this new attitude they have. Being angsty about your oath is kind of the fun thing about Paladins.
In that case I would recommend brutal enforcement of your oath with a twisted sense of the tenets of your oath. Liars get tongues removed. Thieves lose hands. Cowards are made lame. Murderers get killed in horrifying ways. The cruel have their possessions "donated" to the worthy. And so on...
Or perhaps something like the Inquisition. Where they believed they were doing the right thing, but they weren't. (burning down cities of the "heretics", crucifying any "heretic", and so forth)
How would you play an evil Oath of Devotion? Any ideas?
Do you mean in terms of flavor or in terms of mechanics?
Mechanically, I would just rule that everything that affects fiends affects celestials and everything that affects celestials affects fiends (including the base paladin abilities). If you felt like it made sense, you could swap radiant damage for necrotic damage but I would instead just reflavor the evil radiant energy as something fitting the character ("unholy" light in dark shades of purple and red and green). The parts of the paladin that affect undead might seem out of place but it could make sense if you see it as power over undead rather than power against undead.
Thematically, an evil Oath of Devotion paladin might not see themselves as "bad"...just happening to side with Hell and Devils and a Church that is evil. You could have an oath similar to the Devotion oath but twisted in some way.
One idea that you could try is to take the tenets of the code to the extreme. The computer game Ultima V does this with the Virtues to make an "evil" version of the world's "religion". For example, Compassion becomes less about giving to others and instead is "Thou shalt help those in need, or thou shalt suffer the same need." (https://ultima.fandom.com/wiki/Eight_Virtues if you are interested in seeing the other seven virtues) So basically, as an evil Devotion Paladin, you might punish those who don't help others or give to charity or speak falsehoods or act cowardly with harsh punishments because how else are people going to learn how to be part of society?
...and other people are probably going to say just do Oathbreaker Paladin but that's not what you asked...
Let me expand a little bit, I apologize for not being very clear. I have a character who is lawful enough that they won't break their oath, but their faith in the cause of good has been shaken to the core. So they had already sworn this Sacred Oath before this path was kind of dropped on them. So I was really looking for advise of how they could keep the oath and still show this new attitude they have. Being angsty about your oath is kind of the fun thing about Paladins.
Their faith in goodness itself is gone? Or is it just their faith in their god or church?
Canto alla vita
alla sua bellezza
ad ogni sua ferita
ogni sua carezza!
I sing to life and to its tragic beauty
To pain and to strife, but all that dances through me
The rise and the fall, I've lived through it all!
In that case I would recommend brutal enforcement of your oath with a twisted sense of the tenets of your oath. Liars get tongues removed. Thieves lose hands. Cowards are made lame. Murderers get killed in horrifying ways. The cruel have their possessions "donated" to the worthy. And so on...
Or perhaps something like the Inquisition. Where they believed they were doing the right thing, but they weren't. (burning down cities of the "heretics", crucifying any "heretic", and so forth)
Maybe a loyal servant to evil, or you could be a lawful evil devilish who dosen't lie, merely tricks people into doing his bidding.