In the main DC Comics continuity, Mr. Freeze (Victor Fries) has "died" or been incapacitated several times, but one of the most definitive and recent instances occurred at the hands of The Joker. During the "Year of the Villain" storyline, Lex Luthor provided many villains with "Apex" upgrades, but Fries used his to attempt to resurrect his wife, Nora. In a subsequent conflict, Joker utilized a specialized chemical weapon that interfered with Freeze's cryo-suit and unique physiology. However, in the Batman: White Knight universe, Mr. Freeze’s story ends more tragically when he sacrifices himself to save others, with his legacy being tied to the cure for his wife. It is important to note that because comic book timelines are fluid, "death" is rarely permanent. In various animated versions and alternative Earths, Fries has been killed by characters ranging from Batman (unintentionally) to rival criminals. His character is fundamentally defined by his tragic motivation to save Nora, meaning his "death" is often portrayed as a release from his frozen, lonely existence. Generally, if a specific person "killed" him in a recent high-profile run, it was either Joker or the culmination of his own deteriorating condition after failing to save his wife.