While 4th Edition Dungeons and Dragons is primarily a combat game, it’s a role-playing game too. As such, the entire game benefits when some extra thought is put into the character side of character creation.
There are several great models in popular fiction that show the options. Regardless of what you may think of Star Wars, Episodes 1 – 3 or of Hayden Christensen’s acting, the arc of Anakin Skywalker as a young adult lends itself well to role-playing. He starts as a hero, but with clear vulnerability surrounding the women in his life and some issues of pride and wrath. We all knew how his story would end because we’d already seen Episodes IV through VI. In a gaming context, it’s easy to imagine the other directions his story may have gone.
The Lord of the Rings trilogy presents a few other examples, some similar and some quite different. Aragorn, Merry and Pippin are transformed by their adventures, similar to Anakin. Others, like Sam, Gimli and Legolas, don’t change in any fundamental way. Their relationships change, they learn things and become a bit wiser, but Sam is still the gardener who left the Shire when he returns.
Gandalf is a special case: Gandalf the Grey doesn’t change from when he is introduced in The Hobbit until he falls in the Mines of Moria. Gandalf the White’s personality is consistent from when he appears in Forest Fangorn until he departs Middle Earth at the end of Return of the King. In essence, however, those are two different characters. It’s as if the same player created Gandalf the White after Gandalf the Grey failed his third death save.
When creating your own character, first understand what he’s about at that time of life. Next think about where he’ll be at the end of his story. Will he evolve from the wilderness ranger into king of the known realm, or will he go back home and live happily ever after in domesticity? How will his outlook on life change during that journey? Think about the triggers he’s built with. What might throw him into a rage? What will provoke him to fundamentally re-examining his life?
Flexibility is key when it comes to creating a character’s arc for a long term campaign. A player character’s development shouldn’t depend on a specific plot line; while some campaigns focus one PC, you’ll probably have to share screen time and plot involvement with the others.
As you play, you may find that your original concept doesn’t work anymore. That’s okay. Lee Adama in Ron Moore’s Battlestar Galactica had significant arc shifts throughout his story – from Viper pilot to captain of the Pegasus to defense attorney to acting president – that were mostly unplanned when he debuted in the mini-series. The purpose is to add enjoyment to your campaign, so there’s no benefit in sticking to an arc that is no longer compelling.