Greyshire Glacial Grotto, known just as Greyshire Grotto on its map and in the Japanese version, is a dungeon in Final Fantasy XV that becomes accessible in Chapter 3. It is an ice cavern hidden behind a waterfall west of Lestallum. The player can fight a Midgardsormr on the grounds outside it.
Completing the dungeon and retrieving the royal arm is part of the game's main quest. The player receives the quest from Talcott Hester in Lestallum. The player can travel to this location and retrieve the royal arm before talking to him, and if so, he will tell them about the waterfall and the party will tell Talcott they already retrieved the weapon.
"Greyshire" is a Japanese play on words. The Japanese katakana rendering for the English terms "grey" (グレイ, gurei?) and "shire" (シャー, shā?) compound to make グレイシャー (gureishā?), the Japanese rendering for the English term "glacier". This play on words is less obvious in English, so the word "Glacial" was added to its name in in-game text to preserve the second meaning.
Behind the waterfall at the entrance to the grotto.
- Fabled "waterfall cave" tucked away behind Callatein's Plunge. The waters spilling forth from Loch Thriocess conceal congealed caverns whose winding halls have vexed many an adventurer hoping to plumb their depths.
- A legendary sword connected to the royal family is said to slumber within the recesses of the cave, but its existence has not yet been confirmed. Although countless hunters have attempted to follow up on these rumors, the monstrous midgardsormr slithering around outside the grotto has served as a strong deterrent.
Shadows meld into the darkness; all signs of thee are lost
Thy robes and blade of steel, sealed within the tomb of frost
'Til the coming of the king whose aid we call upon
I seal thee as a sign of hope—the light before the dawn
In an unknown time period a king and an Oracle sealed a powerful daemon they deemed a "menace" in a hidden dungeon in the depths of Greyshire Glacial Grotto. The king left behind monoliths for the Chosen King whom he believed one day to be strong enough to banish the threat for good. The king known as the Wanderer is found entombed in the grotto, the time frame likewise unknown. The About the Kings of Yore document in Final Fantasy XV: Comrades posits that royal tombs were erected as a memorial to the king or queen who claimed that land in the name of Lucis, suggesting the waterfall cavern was claimed as part of Lucis during the rule of the Wanderer.
After hearing rumors of a royal tomb being located nearby behind a waterfall, Prince Noctis's party heads out to investigate. They find there is an ice cavern behind the waterfall and scale its depths until they come to a locked door. Noctis has a key for it, and inside they find a royal tomb and Noctis retrieves another of his royal arms: the Swords of the Wanderer.