Frank Mentzer has been lead auctioneer of the GenCon RPG auctions for a very long time. He is not only an expert on all RPG collectibles, but a living TSR legend.
He has revised the red D&D box and co-written T1-4 Temple of Elemental Evil. Mentzer wrote the highly sought after R-series modules — the pre-published R-series modules,
some of the rarest and most expensive items in (A)D&D collecting, bear his signature.
Mentzer also founded the RPGA and was the only employee at RPGA for some time.
Frank Mentzer owns two bakeries and can be found on eBay under the handle of extsr.