Now in its fourth edition, The Boss Hog IV: The Black Prince is WhistlePig’s annual single-barrel straight rye, bottled at cask strength one barrel at a time. Its claim to fame is the finish: this was the first American rye ever matured in Armagnac casks, which layer dried fruit, prune, and Gascon oak richness over a 14-year, 100% rye backbone. Because every bottle comes from its own barrel and is bottled at proof, strength varies slightly from one to the next. Expect big rye spice and French brandy sweetness in equilibrium, with a long, evolving finish. Named Best in Show at the 2017 San Francisco World Spirits Competition, it is a special-occasion pour neat, no ice, and no hurry.