Paladin: Oath of Condemnation
The Oath of Condemnation is one of the anti-mage. It is a warrior who seeks out magic users and ruins their day. This oath can be troublesome if the party has magic users. It is intended to be a bit over the top in its main tenets. In fact the extreme tenets places paladins who take this oath at odds with other paladins and clerics.
In my game world I force Paladins to worship a deity, pantheon, or force. Something other than themselves. This is not the main focus of D&D 5e but I like it in my games. It gives the players a chance to play a paladin in a different way as they are not bond to tenets but to the dogma of who or what they follow.
Using this way you open up the fact that the Oath of Condemnation is self destructive. They seek out magic in all forms and do what they can to destroy it. If by some chance they rid the world of magic they themselves have magic. Knowing this they seek out even the most mundane of magic as the last task is to rid the world of their own magic.
Magic is impure and must be purged in all forms.
Those that practice the art of magic must be hunted and slain.
With these tenets the class is a bit more playable as the paladin only seeks out vile magic. Magic is a tool given by the gods and should only be used in it purist form.
Show other the good of magic, that it can be used to give life and not just take it.
Those who use magic for dark deeds must be stopped. If mercy can be shown, do so, if not they shall pay with their life.
Dispelling Weapon: For 1 minute whenever you hit a creature with an attack they become the target of Dispel Magic. You can end this effect on your turn as part of any other action. If you are no longer holding or carrying this weapon, or if you fall unconscious, this effect ends.
Overcome: You present your holy symbol and speak a prayer, for the next minute creatures within 10 ft. of you loses all resistances and immunities. When you reach level 15 this ability no longer includes yourself or allies and the area of effect is 30 ft.
Know thy Enemy: Whenever you would gain an oath spell you learn two spells of your choice from the sorcerer, warlock or wizard spell list, the spells are always prepared and count as Paladin spells. The level of the spell you can learn depends on your current paladin level. At 3rd level the spells can be level 1, at 5th level the spells can be level 2, at 9th level the spells can be level 3, at 13th level the spells can be level 4 and at 17th level the spells can be level 5.
Sense the Arcane: You can use Divine Sense to locate magic items and detect spellcasters. Whenever a creature you can see cast a spell you know what the spell is being cast and the level that is is being cast as.
Aura of Righteous Magic: Other creatures within 10 ft of you attempt to cast a spell or use a magic item must make a Religion check the DC is equal to your spell save, if they fail this check the spell does not go off but any spell slot is still used. Allies have advantage on this check. At 18th level the range of this aura increases to 30 ft
Mage Slayer: Whenever a hostile creature within reach cast a spell or activates a magic item you may use a Reaction to make an opportunity attack against them.
Mental Fortress: You are immune to charm and fear affects, you are also immune to any effect that would sense your emotions or read your thoughts, as well as any divination spell that you choose. Wisdom (Insight) checks made to ascertain your intentions or sincerity have disadvantage.
Limited Magic Immunity. You are immune to spells of 6th level or lower unless you wishes to be affected. You have advantage on saving throws against all other spells and magical effects.