That tongue, man. That tongue just POPS right out of the picture. I was looking at a thumbnail of it, and I thought the wolf itself was just a sketch - I didn't notice the details - but it's still a really nice contrast.
B&W refers to the fact that the painting is black and white. Only three acrylic colors were used for that, Carbon Black, Titanium White, and Titan Buff to give the B&W toning a slightly warmer tone.
Oh, OK! I should have guessed that, since you talked about choosing to only use color for the tounge in the same scentence. Oh well, thanks for getting back to me CristinaPenescu! I am learning the art lingo, it seems.