Next dnd character idea:
A legit old man. White hair (probs long), beard, muscles (not hulked out, but still strength based class).
Was supposed to be a hero in his youth. Bonus points if the world is steeped in prophecies, predetermined destinies and all that. Not sure on the details of the prophecy, but the short of it is he failed. He didn't become a hero and failed to save a bunch of people.
And so time went on, the world continued. People went about their lives, some remembered the now old man as a failed hero. Most just know him as an old man who never amounted to anything.
Now, perhaps tired of himself being full of regrets. Perhaps invigorated by the knowledge of his inevitable end drawing nearer. The old man picks up his aged weapon, don's his old out of style armour and sets out to the world yet again.
Hopeful to teach any other young heroes his mistakes. And maybe, just maybe. Prove he is hero after all.