The Guildpact is an ancient and epic piece of magic that reverberates across the plane of Ravnica.
Originally conceived of by the lawmage Azor I, it serves as a basis for all Ravnican law, setting statutes and ordinances for each guild so that each of the ten guilds has its own place. Its magic is enforced especially in the most significant representatives of the guilds, such as the League of Wojek. For instance, when a Wojek officer wishes to imprison someone who has directly violated a Guildpact law, it is possible to restrain them utterly. Not even paruns are capable of breaking such a seal.
As a failsafe, the Guildpact could be altered with the agreement of all ten guild leaders.
«Reading it has given me a glimpse of what makes this deeply flawed city so very magnificent.»
The Guildpact itself is 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 draft of the Guildpact, pressed under three inches of magic-treated glass and authored by Azor himself, is still kept preserved in the Old Laws Library of the Azorius Jelenn Column complex.
Not surprisingly, since its signing the leaders since then (including the still-living paruns) have worked hard to find loopholes in which to set forward their own plans. The Guildpact’s spell was finally broken when Agrus Kos arrested Szadek for crimes against the Guildpact, when he tried to destroy it by taking control of other guilds. This generated a loophole because the Guildpact dictated House Dimir’s task as opposing the Guildpact, making it impossible for Szadek to be legally arrested for crimes against it.
The Guildpact’s magic was later reestablished after the events of Dragon’s Maze, but this time in the form of a living being: Jace Beleren. Any law that the Living Guildpact verbally affirms received a magical binding force similar to that of the old Guildpact.
At the beginning of the War of the Spark, Nicol Bolas destroyed the Chamber of the Guildpact by summoning the Planar Bridge within it, disrupting the leylines that maintain the Guildpact’s power. Because of this, Jace lost his abilities as the Living Guildpact, and was thus unable to wield its hieromancy against Bolas. Later in the conflict, the Guildpact was reestablished through a ritual using representatives of the ten guilds and the spirit of Niv-Mizzet, mending the leylines disrupted by the Planar Bridge and reviving the Firemind as a new Living Guildpact.
In Dungeons & Dragons
Most tomes in the DungeonMaster’s Guide provide a bonus to an ability score, but the Tome of the Guildpact is much more than that: A person who attunes to the tome after traversing the Implicit Maze becomes the Living Guildpact.
Tome of the Guildpact
Wondrous item, artifact (requires attunement)
While attuned to the Tome of the Guildpact, you can use an action to activate the powers imbued within it. The Tome works just as the ten charms from every guild in Ravnica at once (the Guild Charms can be found in pages 173-174 of the «Guildmaster’s Guide to Ravnica»), so you can choose any of the spells granted and cast them without expending a spell slot or providing any components. The spell’s save DC is 17 or your own, whichever is higher.
The Tome also contains every spell available in Ravnica as a guild spell as noted in every guild section in Chapter 2 of the «Guildmaster’s Guide to Ravnica». Optionally, if your campaign is using the Renown system, any guild-affiliated NPC acknowledges you as if you had the highest renown score in every guild. As an artifact, the Tome of the Guildpact has also the following random properties: 2 minor beneficial properties, 1 minor detrimental property and 1 major detrimental property.
Destroying the Tome of the Guildpact requires the leylines that cross over the city to be broken first by a major earthqueake or similar disaster.
Coming from a very specific setting as is Ravnica, the Guildpact has literally no place outside that city. Now, having said that, there are some guilds within Eberron that on the surface collaborate with each other, and under the table are more than ready to stab each other: the Dragonmark Houses.
In Eberron, the Guildpact can be the magical embodiment of the Korth Edicts, which give the Kingdom of Galifar a way to enforce them. Unfortunately for the guilds subject to its rule, it can’t be changed anymore, since House Vol is now extinct.
How are you planning to incorporate the Tome of the Guildpact in your campaign? Is there a peace treaty so important to be magically enforced? Are your characters the ones who signed it, or the ones guaranteeing it will be upheld? Can you imagine any amendments to it?