BUT, I am sure that I saw this art before, and it's a Diablo covered with some kind of cape on his back (that's why it looks like penguin, maybe it's made from penguins xD), and this "penguin foot" is a.. tail (tiny a bit, but...).
Has anyone suspected that it's the swirling globe from the Arcane area in Act 2? (not sure if thats the name its been a while). The place in outer space by the boss there. Maybe he'll be involved in linking the 3 games in the storyline or something?