I'd swear that it was actual artwork for the game. :P
I'm not sure if you were trying to emulate the Hearthstone artists, if this is your own style, or if you actually ARE a Hearthstone artist; but it looks great!
I'd try to offer lighting advice, but since there so many light sources I don't think I'm qualified enough to try and make suggestions.
There is a question I have for you if you don't mind elaborating. When someone is able to make super detailed drawings like this, do make them faster because all of your experience? Or does it still take a long time regardless of skill level?
Thanks in advance and excellent work!