Walking Dead #100 Lucille Variants
Image, July 2012.
There are numerous variants for Walking Dead #100, including the coveted Hero Initiative variant, and these two, both featuring "Lucille" on the cover.
The "Lucille" edition was a retailer incentive (R.I.) variant given to select retailers (one per store) who had "large orders and who increased their order the most for issue 100".
All the "Lucille" incentive editions were meant to be signed by Kirkman and CGC decided to stray from its policy of witnessing the signatures and ensuring the comics were not interfered with from signing to encapsulation. However, some unsigned copies surfaced and despite the fact that these could have been signed by anyone forging Kirkman's signature, CGC still allowed any submitted before 9/14/12 to be placed on Signature Series and any after on a Qualified (green) Label hence some forgeries could exist on yellow labels and genuine Kirkman signatures on green labels.
At the time of writing (August 2015), the CGC census had 30 Universal (unsigned) gradings recorded, 1 Restored, 98 Signature Series and, unfortunately, 51 Qualified gradings recorded (as mentioned, many are likely to be genuine Kirkman signatures that some expected to receive on a yellow label). Given that there were supposedly 500 signed, the print run will likely have included additional spoilage, which may account for the number of unsigned copies available (unless some of the 500 remained unsigned).
The other variant featuring "Lucille" is the "Red Foil" Skybound exclusive edition that sold for $250, direct to the public online (hence wasn't a retailer incentive), with limited numbers available each day from Black Friday to Cyber Monday in 2012.
CGC have 131 recorded gradings (circa August 2015) of the "Red Foil" variant from the 250 produced, however, it is worth noting that print run numbers will be approximate as there was likely to have been some overage.
Both if these variants are going for serious money on auction sites such as eBay and, given the small numbers of these, are likely to maintain value long term (so long as the series maintains popularity and the bottom doesn't fall out of the comic market!).