In 'Memoir of the Multiverse,' players assume the role of a quirky historian named Zinnia, who discovers a forbidden tome that allows her to traverse alternate realities. Each reality presents a unique historical twist on familiar events—like a world where dinosaurs developed language, or a 1920s Paris that is secretly run by sentient robots. Players must navigate these bizarre timelines, collecting artifacts, interacting with eccentric characters, and piecing together the true origin of the tome. The narrative unfolds through text prompts, with choices leading to multiple endings based on the relationships Zinnia builds and the truths she uncovers.