I wanted to submit my idea, but I just didn't have the time to write it up. I was just too busy these last 5 weeks. Here's a summary of it though:
The main characters are a human fighter and a half-elven arcane trickster. The fighter, named Jav, was a mercenary during the Last War, but went mad when his party was ambushed while he was sleeping on guard by Karrnathi skeletons, and he saw his twin brother slaughtered and his corpse dragged away to become a skeleton. The arcana trickster, Twil, is a a boisterous, energetic fellow with a ridiculous amount of impractical ideas. He's currently imprisoned in Karrnath because he was caught trying to break into the throne's records.
Jav, who has become wild and barbaric since the end of the war, wandering the edge of the Mournland, resolves to make one last kamikaze attack on the Karrnathi. His attack is fortuitously timed just as Twil is attempt his 498th break-out attempt (yes, he counts). Twil saves the man by knocking him off the wall of the fortress outwards and using his Aberrant Dragonmark of feather fall.
Twil leads Jav, who is still dazed from the whole experience, across country to the nearest lightning rail track. En route, Twil introduces himself (at length), and explains that he is an "Unmarked." Before Jav can absorb this, however, a lightning rail comes speeding by. With fast running and a good jump, Twil gets up on the caboose and pulls Jav up after him. The caboose-worker gladly lets them come aboard, since it's such boring, lousy work back there that he's glad for the company.
They ride the lightning rail all the way to Sharn (with a brief interlude of an attack by a living spell). Just before pulling into the central station, Twil and Jav jump from the bridge the train is crossing and use Twil's aberrant mark to skydive to the lower levels of Sharn. Twil leads Jav deep into the bowels of Sharn, where they meet up with the other "Unmarked": it is a loose-knit brotherhood of those bearing aberrant marks. They specialize in magically-assistedt covert-ops, especially tasks that are too secretive for the Houses.
Jav sees the great city with his host, Twil, and slowly forgets the horrors of his past. Twil gets a commission to steal an artifact from a moving lightning rail train. He recruits a cleric of the Traveller to help them, and acquires the services of an old artificer who has built a make-shift lightning rail vehicle. (A certain amount of "proving-himself" activities are involved.)
They insert the vehicle onto the tracks, and take off after the train. Because their vehicle is so light, they catch up, and begin to climb along the roof of the train. They break in through the roof into the cargo car where the artifact is, but as they're coming down, they are ambushed by Karrnathi soldiers who had been waiting inside. The cleric (who was the only one still on the roof) takes a crossbow bolt, and falls off the train. Twil and Jav are captured.
They are brought before the Karrnathi commander who is in-charge of the protection of this artifact, who turns out to be none other than Jav's twin: Arln. Arln was not in fact killed by the skeletons, for it was he who betrayed the patrol group to the Karrnathi in the first place. He had sold his friends and his twin brother's life for rank in the Karrnathi military. He offers Jav pardon if he will join the Karrnathi forces, but makes no such offer to Twil.
Jav is astonished to see the man whose death had driven him nigh-insane. But as he listens to Arln's overtures of friendship and brotherhood, he realizes that this monster is no longer his brother, and that Twil is now more to him than Arln ever was. He goes into a rage, breaks the bonds holding him, breaks open the side door of the car, and throws himself and Twil out.
Fortunately, Twil has the presence of mind to activate his aberrant mark as they fall.
