The regular edition (that I don't own anymore) features different cover and back cover but the same spine:
|cover of the regular edition|
|back cover of the regular edition|
A variant edition (same illustration used for the cover of the signed remarqued edition) was produced for the SDCC 2014 convention (100 copies, probably not numbered):
My copy is one of the remarqued signed edition limited to 125 copies (same ISBN, 350$, mine being #86) that was issued in October 2014. It features an exclusive signature page with a 5.5 x 4.25 inches (11 x 14 cm) remarqued panel.
|the remarqued panel|
|IDW cardboeard box|
|detail of the sticker different from the regular edition (probably used also for the SDCC)|
|the box is also numbered|
Second and third of cover feature different illustrations. This edition has been designed by Randall Dahlk and edited by Scott Dunbier. The book doesn't feature any introduction. Below there's also a picture displaying the table of content of the first part of this book.
|second of cover|
|third of cover|
Of all the material include in this book, only three original pages have not been retrieved and are displayed here in plain B&W scans (others are of course color scans of the original art). This is not something that IDW has tried to hide as they have indicated the fact in their product description, and these three pages are also pinpointed in the book at the bottom of the page (Hellboy In Hell issue #2 page 16 for this first part). Notice that covers, back covers and variant covers are included.
|zoom of the upper part of the page|
|left the B&W scanned page|
The second part of this book contains early stories including the 10-pages story from John Byrne’s Nextmen #21. Here is the table of contents for this part (B&W scanned pages are page 7 and 19 of The Corpse).
|a double spread page|
The additional material section runs on 7 pages, and also features its own detailed table of contents. The book finishes with Mike Mignola's bio.
|limited to 250 copies|
A second printing of this Artist's Edition has been released in 2017 with a new exclusive cover:
On IDW's site, both 2014 and 2017 editions share the same content description, thus it can be safely assume that the 2017 edition is simply a reprint with a new cover.
In addition to this article, and for more detailed insight about the reproduction quality, don't hesitate to read this Comic Book Daily review by Scott VanderPloeg.