An alchemist who is summoned to serve as Master Reiroukan's Servant. He is the Caster-class Servant in the First Holy Grail War of Fate/Prototype: Sougin no Fragments.
His True Name is Paracelsus von Hohenheim, a legendary physician turned alchemist. At the 16th Century, he is known as a historic figure from the Renaissance Period.
Over the course of his lifetime, Paracelsus devoted himself to the study of medicine and alchemy, leaving behind many achievements and books such as the "rediscovery of the four (five) elements" and the "rediscovery of the three humors," which helped the advancement of Magecraft. A rare individual who went down in both human and magic history. He is also known for creating the original Azoth Sword.
A scholarly magus who is intellectual and calm, Paracelsus is mild and does not enjoy combat He is cool and collected without his posture being thrown off-balance. He shows joy in guiding and teaching young companions, frequently expressing this joy as a smile.
As a rare magus, Paracelsus advocates that human affection is more precious than anything. He regards the modern magi far and wide as the descendants of the pupils that inherited his teachings, receiving them with open affection as if they were his children, and loving them equally as far as the world permits that love. He believes that these descendants are the future, being those that hold infinite possibilities whose accumulation will lead them to the root of the world’s truth. To the common magus individual with an esteemed family bloodline, his words are close to madness, but he does not intend to bend his beliefs. He is, naturally, a mad scientist.
His behavior toward others is gender-independent. Paracelsus quietly swears allegiance toward his Master, though it is more accurate to say that his allegiance is to friendship. In a conventional Holy Grail War where his Master is a magus, he will build an equal relationship such that they aim to reach the Root together. In the case that his Master does not study Magecraft, he will simply offer to be a "friend."
Paracelsus' wish was to be remembered as a great figure in the advancement of human prosperity and be loved by the "children of the future." Another wish he once had for the Holy Grail was "to reach the Root." Furthermore, like how the world was once filled with True Ether, he also wanted to verify his personal opinion that the light of the planet (like that of a holy sword) is indeed a light shining from the Root. It may be that he is currently seeking for atonement instead.
Fate/Prototype: Sougin no Fragments:
During the events of the Prototype Grail War, Paracelsus displayed a surprisingly cruel and remorseless side to his personality by accepting Manaka's offer to switch sides by slaying his previous Master and spiting Assassin by taunting her inability to obtain physical comfort without killing the one who holds her, while simultaneously offering her the corpse of Tatsumi as the only thing she could ever hold. This change of heart was later revealed to have been largely in part due to Manaka's soul-crushing manipulation and intensity. For the rest of the war, Paracelsus would continue to lament on his mistakes in betraying the Reiroukan family, particularly Misaya.
