Although they later changed their mind, initially the Requiem books referenced bloodlines in the base book that they would never develop. This is what I made of one such .

The Mithraic Ventrue claim descent from fabled Mithras, who supposedly founded the Invictus.

There is a very fierce ongoing rivalry with the Atreides bloodline.

Bloodline: Mithraic Ventrue
In the earliest years of the Camarilla, that legendary union of the Kindred into one undead Empire in the time of Rome's greatness, the Ventrue came to power. One mighty Kindred, possibly Persian in descent (according to legend)quite purposefully molded his own blood, and thus that of his descendants, into a form uniquely suited for gaining and holding said power. Ancient and unreliable folklore calls this vampire Mithras...who some say founded not only this bloodline, but the Invictus themselves...for a title of the *god* Mithras was Sol Invictus, the invincible sun. Such musings are but fable, in these modern nights, for no elders remain that recall those nights clearly. Too many torpors have passed, too many long unwaking nightmares. What is known, is that the Mithraic Ventrue still have their creator's aptitude and lust for power.

Parent Clan: Ventrue (Although some claim the Ventrue themselves are just a Daeva bloodline.)
Nickname: Tyrants

Covenant: Most commonly Invictus. Lancea Sanctum is second most common as a traditional path to power, followed by the young turks who choose Carthian as a quicker route. Few choose the seeking after mysteries typified by the Ordo Dracul, and fewer still the pagan spirituality of the Circle of the Crone.

Appearance: Much like the Ventrue, their parent Clan. they tend to dress very carefully, and evoke specific reactions with their appearance and dress.

Havens: As Ventrue.

Background: Physical beauty is important to the Mithraic ventrue, as it directly affects good impressions, but personal presence and a knack for wielding power are *more* important. No Mithraic Ventrue will Embrace or sponsor any individual who does not display impeccable taste, judgement, ambition, and political savvy. They are,
in effect, the Ventrue's Ventrue.

Character Creation: The Mithraic Ventrue value Social Attributes and skills above all, but weakness in any area is not tolerated. All forms of power must be cultivated, because these Kindred cannot accept defeat.

Bloodline Disciplines: Dominate, Majesty, Resilience, Vigor

Weakness: In addition to the standard Ventrue weakness, Mithraic Ventrue *all* possess the derangement Megalomania, manifesting in the "James Bond Mastermind" style. They must always accrue ever greater power, and everyone is either a minion or a rival. Even minions must be watched, of course, as they might *become* rivals.
(As page 190 of the Requiem tabletop book: When the character loses a contest of any sort to someone that character considers a social inferior, they lose a point of willpower, due to shame and self-loathing. In the case of Mithraic Ventrue, it further means that if they are actually *taunted* by said inferior after a loss, they suffer a -3 penalty to resist entering an anger frenzy directed at the offending individual.)

Organization: The Mithraic Ventrue, offspring of Sol Invictus, follow their parent clan's organization. Few outside the clan know of the distinction. Canny Kindred, however, will notice that Domains controlled by Mithraic Ventrue are much more strictly controlled and organized than other domains.

Concepts: As parent clan, but more so.

pdf here: https://www.patreon.com/posts/65784608