Oppenposting refers to the surge of memes featuring J. Robert Oppenheimer, specifically focusing on Cillian Murphy's haunting portrayal in Christopher Nolan's 2023 biopic. These memes typically lean into themes of deep regret, existential dread, or the shocking realization of unintended consequences, often paired with the famous quote, 'Now I am become Death, the destroyer of worlds.' The template's popularity skyrocketed during the 'Barbenheimer' cultural phenomenon, where the film's somber, black-and-white aesthetic provided a stark comedic contrast to the vibrant world of Barbie. It is widely used today to represent a 'thousand-yard stare' after someone makes a decision they immediately realize was a catastrophic mistake.