Which grape variety is traditionally known as the main grape in the wine called "Bull's Blood"?

Bull's Blood, or "Bikavér" in Hungarian, is traditionally associated with the Kadarka grape variety. This wine is produced primarily in Hungary, especially in the Szekszárd and Eger regions, where Kadarka is well-suited to the local climate and terroir. The grape contributes floral and fruity notes to the wine, enhancing its complexity and character.

Kadarka has historical significance in Hungary, often being celebrated for its quality and ability to produce age-worthy wines. The blend typically contains other varietals as well, but Kadarka is the cornerstone that defines its style and reputation.

While other grapes like Malbec, Sangiovese, and Zinfandel are notable in the world of wine, they do not have the same direct connection to Bull's Blood as Kadarka does, making the latter the quintessential choice for this particular wine style.