House Name Einzbern
Background The Einzbern are one of the three founding families for The Holy Grail war. They poured their magical trait of wish granting into the holy grail granting it the ability to grant impossible dreams. They're also responsible for creating a host for the grail for each war.
The Einzbern have become masters in the field of Alchemy, their skill is without equal. However because of this they have neglected other fields of study completely, and have become severely handicapped when it comes to combat magic. However this hasn't been for naught. They've been able to achieve what many can only hope to, the creation of synthetic human life. The Einzbern are the only House capable of creating Homunculi.
They wish to recover the grail so that they can recover the lost miracle that their family once possessed: The ability to cast magic without even knowing the spell.
Homeland Germany
Bloodline Alchemy, specifically Alchemy concerning living organisms.
Homunculi
Upon character Creation a mage of the Einzbern family can choose to be a Homunculus. Homunculi are just like regular humans only designed with a specific task in mind. As such they're able to cancel out a negative trait of a spell or servant, as their body is designed to handle that specific circumstance. (I.E a Homunculus could be designed to negate the mana Drain of the Berseker class, like Illyasviel. They could be created to be able to befriend Gilgamesh. They could even be created to negate the negative effects of their house curse!)
This will be heavily monitored.
Family Curse Any combat skills used by a member of the Einzbern family is considered to be one rank Higher as far as cost is concerned. (An B-Rank attack Spell will use up your A-Rank spell slot.)