Six!
I was applying for a job at Gram Games in London. I thought I’d be fancy and did some fan art based on some of their mobile games. I didn’t get the job, but here’s what I did. 
Screenshots of the game Six!
I made a basic 3D mock up, and then painted on top of it in Photoshop.
Merged!
Same deal, looked at screenshots of the mobile game, did a 3D mock-up, painted on top in Photsohop.
Game screenshots
3D mockup.