It is awesome, so epic! You pull out the sense of scale so well, and the last lightinf you added improves a lot the reading.
I would like to point out, if it helps, a coiple of things:
His right hand looks a bit broken (like, by the wrist), if that was the idea, then don't mind this, but if its not, maybe it would help rotating it just bit clockwise.
The lava crying and blood coming from the chest wound looks to artificial to me, the crying doens't looks like liquid and the blood doens't follow the form of his abs, both of this is because they are just straight lines, altough I think it may be just beacuse your aren't done yet.
And finally, the long tall format may play against you, I know it helps a lot to evoque that sense of scale, but it forces you to scroll on most devices to get the entire picture, so the scale in conveyed only at a second read, when you already scrolled and saw those poor tiny humans burning there. I know it would be harder to make it work on a shorter canvas, but it not may be impossible.
I hope this help, even just a little.
