Long Ago in the Land of Ooo

Dramatic yet bland title because I have no idea what to call it. I've been trying to do fan art for AT for a long time, but this is the first thing that's gotten past the sketch stage.
Young Marshall and Lord Mo-chro leaving the Ice Kingdom. Use your imagination for context.

Also, if anyone wants to point out any flaws and faults in this thing, I'll be happy to hear it. Don't be shy, I don't bite.