I'm currently working on a short story/novella called "Warrior, Wizard," which is about two friends (who are, as you may have guessed, a weapons user and a magic user) who end up struggling with the growth of their strength at different times. It's based around the concept of "Linear Warriors, Quadratic Wizards," or the fact that in gaming (and other forms of media, but this is most noticeable in tabletop and video gaming), warrior classes develop at a steady rate while wizard classes start weak but become insanely powerful.
This is a different discussion altogether, though. I could go on about it, but all that's really important to know is that I'm writing a story where one character always feels like they can't compare to the other, but the balance shifts halfway through.
When I set out to write this story, I knew from the beginning that I didn't want to tell it in chronological order. I wanted to show that, as much as my mage struggled with feeling inferior at first, my fighter felt just as inferior later on. I didn't want a gradual shift but a side-by-side comparison. And so I set out experimenting with anachronic order.
Anachronic order, or rather, nonlinear order, can make for a wonderful storytelling device. It can be used wonderfully a lot of different ways for a lot of different reasons. In "Warrior, Wizard," it's to show that the two aren't really as different as they think and that both have their periods of feeling inadequate. It provides a sense of dramatic irony. While the mage feels like she's a burden when she needs saving, the audience knows that she's the one saving the fighter a few years down the road. It plays the two dynamics against each other.
I'm not entirely certain how I'm going to tell the story quite yet, though I'm leaning towards finding an important event near the middle of the timeline and working forwards and backwards from there. How I'm writing it, however, is chronological order. It's maybe not as fun to write, but I think that I'll need to in order to figure out what exactly it is that happens so that, when I'm working on the order of the segments, I can refer to past events that have happened in-story. It'll be less fun, but will also mean less rewriting.
But let's look at some other bits of media that have already used the device. Four, to be exact: a movie, a live-action TV show, an anime, and a book. All from different mediums (though you could make an argument for television being the same medium, even though one is animated and one live-action), all from different genres. All use the device in a different way, but all to wonderful effect.
The first one I want to talk about is Memento. Memento is a movie about a man who, after an injury following the death of his wife, loses the ability to make new memories. The movie actually has two interspersed timelines: one moving forwards that consists mostly of the protagonist giving exposition, and one moving backwards, which details most of the action in the film. The timeline moving backwards shows us exactly what is going to happen, but since most of the scenes begin in medias res (or "in the midst of things"), we're not left wondering what's going to happen, but how it's going to happen, and how the current scene will lead into the previous one. Not only does the narrative choice make the movie interesting, it's stylistic. The story is told in anachronic order to mimic the protagonist's short-term memory loss. In each scene, we only know as much as the protagonist does at the time.
The next one is LOST, that show about the people who land on an island and then there's mystery and more mystery and magic and science and what's that in the woods and time travel and so on and so forth. As easy as the show is to poke fun at for its convoluted plot (and its inability to get around to answering questions and its constant dropping of plotlines and WAAAAAAAAALT and so on and so forth), I absolutely love the show for two reasons. The first is the attention given to characters. But the second is the narrative style, which was what most people love about the show and has been imitated frequently since. Every episode of LOST tells two stories: what's going on currently with the people on the island, and what happened in their lives to bring them to that point. It becomes clear early on that all of the survivors of this plane crash are connected in some way. The flashbacks are all out of order, and it's used to give you the story piece by piece.
The next story I'm going to talk about is House of Leaves, by Mark Z. Danielewski. While there is plenty going on in this story, anachronic order is used to provide a sense of confusion. Most of the book is framed as notes on an incomplete dissertation on a documentary. It's unclear whether or not the documentary itself uses anachronic order (though it very well might, especially if it's interspersed with interviews that reveal the nature of the house earlier than the narrative does), the notes and dissertation perspectives are fractured, with the dissertation being compiled of bits and pieces that may not have originally been parts of the same chapters or even intended to go in the final product, while the notes seem to jump around in chronology some as well. In House of Leaves, this adds to the general surreal feeling of the novel, where it's hard to tell what all is true or real.
But perhaps my favorite example of anachronic order is in the anime Baccano!, which uses it masterfully. The show begins with a young girl working with a newspaper trying to figure out how to tell the series of events surrounding the Immortals. It takes place over three years (1930-1932). Each year has its own arc, with 1930 focusing on the (re)creation of an Elixer of Life and a few mafia families, 1931 focusing on a multi-party train heist, and 1932 focusing on the Genoard family, with the young daughter searching for her asshole of a brother. All three storylines are connected through the characters, and even the individual arcs themselves are told out of order. In fact, the very first episode shows scenes from the end of each of the storylines. Baccano! is consequently very hard to follow the first time around, but there's a point to the order the story is told in, which is explained in the very first episode: as in life, there is no true beginning to a story (in fact, the 1930 storyline actually begins in 1711), nor are there main characters. The jumping around from period to period focusing on multiple characters emphasizes this perfectly. A character described as "main character-ish" is only the debatable protagonist to one story (in which he's no more crucial to the plot than many other characters), and the characters with perhaps the most screentime are connected to all three plots--but largely just tangentially.
Basically, as confusing as it can be, I love anachronic order. It's a wonderful way of framing a story, if done for the right reasons. So now my job is to figure out what order to tell "Warrior, Wizard" best. Randomly? Jump around between relative stories? From the ends to the middle? Or, as I'm leaning towards, from the middle to the ends? I'm probably going to go with that last one, since it will provide the most contrast. Now I just have to write the darn thing.