Killer Frost is a name used by several female supervillains and superheroes appearing in comic books published by DC Comics: Crystal Frost, Louise Lincoln, and Caitlin Snow. All three usually have some connection to the superhero Firestorm.

Doomsday Clock is a 2017–2019 superhero comic book limited series published by DC Comics, written by Geoff Johns with art by penciller Gary Frank and colorist Brad Anderson. The series concludes a tangential story established in the New 52 and DC Rebirth, and it is a sequel to the 1986–1987 graphic novel Watchmen by Alan Moore, Dave Gibbons and John Higgins, making it the first official crossover between Watchmen and the mainstream DC Universe.