The Einzbern, a bloodline that once wielded the Third Magic, but lost it at some point in time. For such an old lineage, they surprisingly have no branch families. Their Sorcery Trait is the flow/transference of power.
About 1,000 years ago, the Einzberns started a quest to recover their lost miracle but eventually came to realize that they would never succeed by themselves and thus sought outside help. The result was the establishment of the Heaven’s Feel ritual 200 years ago thanks to the help of the Makiri and the Tohsaka. They were the ones who built the Great Grail of Fuyuki and also the ones left in charge of producing a new vessel of the Holy Grail for each new Grail War.
The Magecraft of the Einzbern family, which follows the Thaumaturgical School of Alchemy, is based on the creation and refinement of substances and the focus of their studies lies solely in the structural manipulation of precious metals. They know healing Magecraft, but as alchemists this is used not for the sake of recovering the flesh of injured people, but rather to lessen the great burden felt by a subject who received an organ that was tempered with magical power and help his body get used with the newly transplanted organ. Because, with the craft of the Einzberns, magical energy becomes easily dispersible, buildings that are sealed off with soil or stone are the ones most desired by them to install a workshop.
The Einzberns are well known for being excellent producers of homunculi. Even the ones that are regarded as failures by their creators are still superior to even 100 magi. The Einzbern homunculi have their functions determined during the design stages and are born with bodies and minds optimized to perform their purposes.