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D-IX

D-IX was a methamphetamine-based experimental performance enhancer developed by the Nazis in 1944 for military application. The researcher who rediscovered this project, Wolf Kemper, said that "the aim was to use D-IX to redefine the limits of human endurance.".

Nazi doctors were enthusiastic about the results, and planned to supply all German troops with the pills, but the war ended before D-IX could be put into mass production, though it did see limited use among a handful of Neger and Biber pilots.