I did two versions of this particular piece: an uncut---larger version, and a signature appropriate version.
This is the signature version.
Premise of the image itself:
Before the war, the previous Avatar and the Firelord were friends---childhood friends. Over time, the relationship soured, and a war emerged and that Avatar---Roku, perished at the misfortune of having unfinished business involving his former friend---Sozin. The burden of bringing balance was passed on to the next yet to be reincarnated Avatar---Aang, whose disappearance was marked with 100 year's passing. When he would re-emerge, it would be his priority to balance a war torn, caught in chaos, world. It was the destiny of this Avatar, and the descendant of those former friends---Zuko---to set things right once again and restore peace.