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The DNA Sacrament was the sharing of Aenea's DNA-modifying virus that was given to her by her father, the first John Keats cybrid Johnny. It began as Aenea started sharing tiny amounts of hre blood among her followers in worlds such as T'ien Shan, and was later spread by her followers to billions of humans on hundreds of worlds, creating a new social, religious and political group known as the Aeneans. It was normally given out mixed in with wine.
Within days, those who shared of the sacrament began developing new abilities to access The Void Which Binds, including the infinite amount of memories that inhabit it, and to "hear the song of the stars" - which means being able to freecast.