Twenty-five years after Doom's landmark release in 1993, lead designer John Romero returned to his most iconic game with the release of SIGIL, a brand-new episode spanning nine levels of intricate maps and grueling battles. In 2023, Romero celebrated Doom's thirtieth anniversary by unleashing SIGIL II, the game's sixth episode--and its most challenging to date.

Bestselling author David L. Craddock plunges readers into the darkest pits of Hell to reveal the design process that guided development of SIGIL II's diabolical levels—and the driving force behind Romero's tireless journey to challenge himself in the industry he helped pioneer.