The Ensanguined Font is an Unexplored Territory in Xenoblade Chronicles X. It is located in Noctilum, in a cave that runs between the Waterway Tangle and Garden Spring. It is large enough to permit Skell's entry and must be visited during Frontier Spirit. At night it is the sole location of the Spore Filiavent. As with all Unexplored Territories, its discovery merits an achievement ("Colors of the Ensanguined Font").