Shadow Galactica been played by two actresses, Haruko Yamaguchi and Megumi Wakamatsu. and appear only in Act 48 of the manga. Sailor Lethe is named for a naiad in Greek mythology, and for a river of the Greek underworld where dead souls go to forget their past lives before being reincarnated. Sailor Mnemosyne is named for the Titaness of memory, the mother of the muses, as well as another river in the underworld which brought remembrance and omniscience. Sailor Lethe has an attack called "Galactica Myosotis Alpestris", which she used to attack Usagi. Myosotis alpestris is the name of an alpine species
Barge of the Dead travel to Gre'thor on a barge steered by a ferryman". Religious studies scholars Ross Kraemer, William Cassidy, and Susan L Schwartz interpreted the representation of Gre'thor and Klingon spirituality as borrowing from Norse and Greek mythology, specifically the crossing of the rainbow bridge Bifröst or the river Styx. Exploring the influence of the Greek story of Odysseus (Latin: Ulysses) on "Star Trek: Voyager", the Classical philologist Otta Wenskus points to Siren-like creatures who call out with the voices of those loved by those on the barge. Though the motif of a barge and ferryman is not present in Homer's portrayal