One of five living Magicians capable of True Magic beyond modern science or Magecraft. Appears in the Heaven's Feel route of Fate/Stay Night. He's one of the founders of the Clock Tower and the Magician of the Second Magic, he holds the title of Wizard Marshal in the Mage's Association. He is known for defeating the Crimson Moon in battle.
Known by numerous nicknames, including Zelretch the Wizard Marshal, Zelretch of the Jewels, Old Man of the Jewels, and Kaleidoscope, Zelretch's origins and details as to how he reached the Second Magic are unknown.
In 300 AD, he defeated Brunestud of the Crimson Moon, the King of Vampires, simply because of his dislike for Brunestud. He rallied the mages of the world and led them into battle. When the Crimson Moon attempted to drop a mirror image of the moon on the Earth, Zelretch used the Second Magic and Jeweled Sword Zelretch to create a virtually limitless Ether Cannon to fight back. In 500 AD, he was one of the founding members of the Clock Tower. The Department of Mineralogy "Kischur" is named after him.
In Tsukihime Worlds:
In Tsukihime worlds Zelretch had his blood sucked during his battle with Brunestud the Crimson Moon, resulting in the Wizard Marshal being turned into a vampire classified as one of The Twenty-seven Dead Apostle Ancestors. While he emerged victorious, or it could possibly be said it ended in a draw, he paid a heavy price. He became extremely weakened because of the battle, aging him severely and causing his powers to diminish.
Despite his status as a vampire, Zelretch still remains an ally of humanity and the nearly extinct race of True Ancestors. He was one of the Magicians who would be summoned to witness the births of princes and princesses like in ages past, and one such event was the coming of age ceremony of Arcueid Brunestud eight hundred years before Tsukihime. Along with his friend Caubac Alcatraz, they appeared before her and Zelretch, having "sent away" the King of the Moon, was very intrigued by her. He smiled and said "This is why life is interesting" upon seeing her. She also took an interest in him due to it being her first time seeing a smiling face.
He told her that she will sleep until she becomes an adult, and she asked him why he was smiling, because no one at the castle ever smiles. He said that people smile when they enjoy their own lives, which she did not understand due to her unique upbringing. When asked what is enjoyable and when she will understand, he replied that it was a fifty-fifty shot that she would come to that realization, and that due to her long life, she would have many opportunities. Understanding is something gained by chance, like walking alongside the road and tripping over a rock, and once something is understood, it is no longer anything special. She did not and could not understand, but he said to her that "One day you will notice that life is fun just being awake."
