Sacred Shroud is an item in Wild Arms 4 and Wild Arms 5, one of the four items needed to fight Ragu O Ragula by breaking his seal.
Wild Arms 4[]
In Wild Arms 4, the shroud is dropped by the optional boss Sapphire Drake at Autumn River and must be brought to Etemenanki along with Holly Crown, Obsidian Spear and the Crystal Tear.
Wild Arms 5[]
In Wild Arms 5, the player has to bring the shroud to the deepest part of the Abyss along with the Holly Crown, Obsidian Spear and Jasper Pillar.