Feels like Halloween all over again...
Bicycle Brimstone was the first deck from Russell Kerchval at CCCC, and it was one of the earliest decks on Kickstarter. A true black deck with red and gold design work, some creepy-looking demonic court faces and the "X" card. Quicksilver takes the same design theme with a back modeled from the mercury symbol (Brimstone was sulphur, I think) in a blue/silver color theme.
Bicycle Karnival Dose Redux was, as the name implies, a reworking of the Sam Hayles designs for the Karnival Dose deck - at the time, the Dose was the first Karnival deck to NOT have the Bicycle name on it. The re-do included a new, double-sided back with a semi-subtle one-way mark and the addition of the Bicycle name. The faces for both remained the same, a really creepy-looking "filthy Victorian-age lab" theme through all of the cards with the requisite skulls (for what BBM design is complete without them, right?) as well as taped X's over the court cards' eyes. Not a black deck in type, but certainly one in spirit.
Voters who comment on their choice are entered in a random drawing for forum swag - see
this topic for the rules.