Fantastic pic in general, but... I'm kinda confused about the barbarian's pose and what emotion he's supposed to be expressing. And what's he looking at? Is there a Starbucks off to the right? Still, great concept. If I had to give constructive criticism it's just... for the centerpiece of the picture, the barbarian's just kind of there, not really fitting in with the theme of the rest of the image. Congrats tho!
He's just arrived in Westmarch and he's walking the streets looking around calmly, but he's ready to fight if need be, he's not "just kind of there". Not every Barbarian illustration has to have him foaming at the mouth in a battle rage.
from what i can come up with the title, the barbarian seems to have just defeated defeated diablo himself, and as he walks thru town with the trophy, he comes across with a new adversary, malthael, as it is indicated in the cyan/dark fog on the barb's foot area, also it is he who casts the tall shadow stretching across the barb's chest. I'm also guessing the purple-ish light is somewhat a bounce light from malthael's clothes, or even his aura, the bodies on the foreground also seems to be an indicator that something took place while the barb was away.