The Guildpact

Ravnica is set upon a nexus of powerful leylines of magic. Each leyline surges with the magical energy of a certain variety or "color." If the civilization atop the leylines becomes unbalanced, the leylines surge and causes powerful arcane storms and natural disasters so powerful they threaten to tear the world apart. Upon discovering this, the sphinx Azor, founders of Azorius, moved to create the first guildpact to ensure the balance of arcane energy in the leylines.

The First Guildpact

The First Guildpact serves as a basis for all Ravnican law, setting statutes and ordinances for each guild so that each of the ten guilds has its place. The Guild Founders or "Paruns" pooled their magic to create a treaty that could enforce itself. Certain agreements in the Guildpact, if broken, brought automatic magical consequences on those who defied them.
Authorized guild representatives can enforce the Guildpact's magic. For instance, when an Azorius officer wishes to imprison someone who has directly violated a Guildpact law, it is possible to restrain them utterly. Not even beings of immense power like paruns are capable of breaking such a seal. As a failsafe, the Guildpact could be altered with the unilateral agreement of all ten guild leaders.

The original Guildpact is an arcane tome housed in Vitu-Ghazi. It is a large book containing both the text of law, as well as explanations of the decisions made during the founding of the guildpact. The law was focused upon an ancient, primeval living document signed with blood and magic by each of the paruns to represent their willingness to work together to hold the city together.
The first guildpact was broken when one of the Parun found a way to work around the arcane law and created a loophole which began triggered the Supreme Verdict, a series of uncontrollable arcane storms.

Teysa's Guildpact

A new non-magical Guildpact known as The Official Accord and Guidance of the Guilds of Ravnica or the New Accord of the Guild of Ravnica was drafted by Teysa Karlov. Since it was not backed up by magical forces, no guild took it seriously. Magical storms ran wild, destroying much of Ravnica.

The Living Guildpact

The Guildpact's magic was later reestablished in the form of a living being: Jace Beleren. Any law that the Living Guildpact verbally affirms receives a magical binding force similar to that of the old Guildpact. Although Teysa's Guildpact was now verbally affirmed by the Living Guildpact, its power was not binding in the chamber of the Obzedat, the Orzhov ghost council.
It states in part: "By order of the united guilds of Ravnica, it is decided that the betterment and progression of any one guild over another may be seen and understood as an act of war. Should proof of such subversion be discovered by another representative of any other guild, it may be confiscated and turned over to the Living Guildpact for investigation."

Type

Magical, Honorific