Main Timeline

When Szadek killed Savra vod Savo it created a loophole in the guildpact. Killing a guild leader was a crime againt the Guildpact but at the same time, House Dimir's purpose had been stated as to have to oppose the Guildpact. Thus, his action being both in accordance and in violation of the document, the magic that held it together ceased to exist and the Guildpact was broken.

After years without a real Guildpact, it is discovered that Azor had prepared a contingency plan should the original Guildpact ever be broken. It consists of a giant riddle inside a structure called the Implicit Maze in which all ten guilds have to participate by selecting a "runner" who will compete for them. After a lot efforts, alliances and treasons, every single runner manages to reach the maze's end and is imbued with the Supreme Verdict, a spell that could wipe out all the guilds at once. Before any of the runners has the chance to even think about using it, Jace Beleren uses his telepathic abilities to connect the minds of the ten runners making them realize that each and everyone of them has people they care about and that the devastation would be more than merely physical.   Considered to be the real savior of what had been a test all along, Jace Beleren is imbued with the power of the Guildpact and as such becomes the Living Guildpact. From that moment on whatever he says magically becomes the law on Ravnica.