https://californiaprimerecovery.com/lsd-and-mdma-what-is-candy-flipping/
"Candy flipping is a term used to describe the practice of combining LSD and MDMA during a psychedelic experience. It involves taking both substances simultaneously or in close succession to enhance the effects and create a unique altered state of consciousness. This combination is believed to create a synergistic effect, where the individual experiences the hallucinogenic properties of LSD and the euphoria and empathy associated with MDMA."