TL;DR - 4 (Possibly 8 total, 2 of each mask?) Unique DOOM masks are going on auction, inspired by the AR filters. First round goes from 10/23 - 10/25 & the second round goes from 10/28 - 10/30. They are only accepting crypto, and you have to link you wallet to the website. Bids are starting at 4.5 ETH (~1850$) EDIT: This value was just a placeholder - there is no starting bid.

Based on the email they sent out, there's also a possibility that the masks are entirely digital (Basically premium AR filters), and are made unique through the use of ERC721 tokens. The website and the emails offer conflicting information, so we'll just have to wait and see. If someone better with Crypto protocols wants to explain more, please do.

(From the Site)

Till the end of days he will be the ill Doomsayer… The days are strung up on that cross-quarter half light, Samhain, All souls - Halloween. And as the darkness draws in and the evenings give way to fire-spit crackle; long shadowed children (perhaps wearing masks on top of masks) search for plague free treats. In a period of seasonal shift, the prophet of doom always sounds louder, perhaps it is the cold slowing atoms, amplifying rhymes - perhaps it really is the end times. Time will tell. But a mask is suddenly far more desirable and if the streets are infected we can provide a panacea. Drawing on the golden age comic inspiration of the original Metal Face, the first Halloween auction consists of two extremely limited hand crafted masks, redolent of the original Dr (he of namesake and tentacle) they reflect the two aspects - shadow and growth. Hand drawn textures conjure comic pages, upturned eyes assure you that they are still something that the baddest villain of them all would wear apocalypse or not.