The Azorius Senate

Founded by parun Supreme Judge Azor I, a sphinx lawmage who authored the original Guildpact,
the Azorius Senate functions as Ravnica's official government and creates Ravnican laws.

Believing their legislation to be the singular force that prevents Ravnica from descending into chaos, the Azorius Senate mediates and regulates the activities of all of the other guilds and the plane despite their numerous decrees, such as the Codex Infinatum, being ignored.
The Azorius Senate is characterized as being aloof, bureaucratic, excessively formalistic, and fastidious, spending hours upon hours with legal documents and ensuring action, if any should occur, stringently adheres to protocol. For such reasons, the Azorius are deeply disdained by Ravnicans, whom the Azorius believe will effect a change and subsequent crime, chaos, and general decline in civic life. The Azorius are said to act through inaction.

Azorius decks are primarily built around evasion and prevention while making sure your creatures swing in as much as possible.

• Main races: birds, griffins, sphinx, spirits, vedalken, humans
• Main classes: knights, soldiers, advisors, wizards, detectives

Clan Ojutai

As the new leader, the elder dragon Ojutai demanded that the records of the Jeskai be edited to rewrite history in his favor, declaring himself ruler and founder of the clan.

The humanoids of his clan revered the dragons as the epitome of age, wisdom, and martial strength, seeking their guidance and believing that, by following Ojutai's edicts, that they would in another lifetime be reborn as dragons.
The elites of the clan were the long-lived Skywise dragons. They were aloof, solitary, and graceful. The teachings of the dragons (and of Ojutai in particular) were seen as the pinnacle of attainable wisdom and the entire clan was structured around gaining enlightenment from the Great Teacher himself.

• Main races: dragons, orcs, humans, birds
• Main classes: monks, soldiers

The Guidelight Voyagers

The Guidelight Voyagers are a racing team from an unknown plane that competed in the Ghirapur Grand Prix.

The Guidelight Voyagers are an uncanny collection of automatons captained and coordinated by a single mind: a machine that calls itself "Mendicant Core".
Mendicant Core and the Guidelight Voyagers have been an enigmatic, fan-favorite team after their appearance in the first multiplanar run of the Grand Prix. Rumors follow them, with the ignorant fretting they might be some new form of Phyrexian and the curious wishing to disassemble them in search of a maker's mark.
The truth is far more mysterious and even more tragic: They are lost, with Mendicant the sole sapient being amongst the machines he attends.
They race the Grand Prix searching for a way back home, each member of their racing team functioning as one of their limbs in a vast network of intelligence, lost in and alien to the Multiverse.

• Main races: Robots
• Main classes: artificers, pilots

The College of Fatehold

Fatehold is the School of Future History at Hexhaven University on the Echoverse version of Arcavios. It is aligned and the counterpart of Lorehold. The founder of the school is TBA.

Their mages are predicting all possible futures, looking for an optimal end state. They then manipulate the present to change the course of history toward that optimal end point.
Not much else is known yet, due to the set and story not being released yet.