This awesome customized imperial knight, called "Iron Werewolf", is an incredible piece built by ComradeQuiche. I had been following his progress throught his Instagram Account (browsing Instagram by some warhammer tags it is so easy to find nice photos) but this last weeks have been really busy and I hadn't seen the finished results... and oh, boy!
Such a great modding (and 3D printing) job that Forge World should hire him to design an official resin kit. The painting is also so well done that makes the miniature shine even more.
There's a nice gallery and details on the construction of some pieces on this Tale of Painters article.