Big Hat Logan

Big Hat Logan is a sorcerer and NPC vendor in Dark Souls. The player first learns of Logan from Griggs of Vinheim, another sorcerer who has followed Logan to Lordran and refers to the elder magician with great reverence. Both men hail from the prestigious Vinheim Dragon School, an arcane college responsible for many of the world's finest practitioners of magic. Despite his renown among his peers, Logan is famously antisocial and wears an oversized hat to shield himself from any unwanted attention, preferring to devote himself solely to his studies. Logan traveled to Lordran to find the Duke's Archives, the library of Seath the Scaleless and a trove of obscure magical knowledge.

Logan can be found imprisoned in a cage behind a brick wall in Sen's Fortress and expresses his gratitude upon being released by the player. He returns briefly to Firelink Shrine to become an NPC vendor of advanced sorceries, but Logan soon leaves to resume his quest for the Duke's Archives. However, he is again captured and incarcerated in a large cell inside the Archives prison. After being freed a second time, Logan finally reaches his goal and begins studying the Archives' magical texts while offering to sell new Crystal-based sorceries to players with sufficient Intelligence.

Like Seath before him, the intense study of such a vast amount of magical knowledge eventually takes a heavy toll on Logan's sanity, as evidenced by his diminished perception of time and gradual inability to recognize the player character. After the player defeats Seath and buys all of Logan's available spells, Logan will succumb to his madness. He leaves his usual spot in the Archives and appears in Seath's first boss chamber, gibbering and naked save for a loincloth and his trademark hat. He will attack the player on sight; killing Logan this way awards the player his hat and Tin Crystallization Catalyst as well as the White Dragon Breath spell. The remainder of his armor and Logan's Catalyst may then be looted from a chest near his former location as an NPC vendor in the Archives.