- It can be an external condition altering your state of mind (Durge be like)
This hits at a very interesting topic even D&D rarely touches. There is magic in D&D that can instantly and permanently flip your moral alignment like
Compel(though that's from 3e, some approximation of this exists in 5e as well I believe)...it's very rare and I'm not even sure how many DMs even bring it up at all in their campaigns...but it does exist. You can play as the most pure good of Paladins, but run into the wrong enemy, roll a nat1 on the wrong saving throw and you could instantly become pure evil. And undoing the spell can be very difficult as it would require someone else to that same spell, a wish spell, or a miracle.
Here we, go, in 5e if you attune to the
Book of Vile Darkness you must pass a DC17 Charisma saving throw or your alignment instantly flips to neutral evil.
