Also known as: 自立観測型存在証明システム・ムネーモシュネー, ムネーモシュネー(Fate)
Character appearing in the Lady Reines Case Files event of Fate/Grand Order. She is the personification of a failed computer program designed to confirm Fujimaru Ritsuka's existence during rayshifting that was left uncompleted and unused during the events of the first Grand Order. She manifests her grief at being left unused by trapping Ritsuka in a Singularity wherein she tries to alter their memories of Leonardo Da Vinci (Fate), whose appearance she borrows. A fragment of her was later mixed with Hephaestion (Fate), giving her the true name of Hephaestion Mnemosyne.
Character Design: Simosi