The ten guilds are the lifeblood of Ravnica, making up the foundation of its society. They are voluntary associations led by guild masters, but that's the extent of their resemblance to the craft and merchant guilds found on most Dungeons & Dragons worlds. They include many different kinds of organizations:

Citizens of Ravnica aren't born into guilds. An individual can choose to belong to any guild—or no guild. Some guilds, such as Selesnya and Boros, actively recruit new members, while others simply accept those who seek membership. People within a family might join different guilds, which can lead to strong connections between the guilds in question or to painful animosity in families whose members follow different paths.

Even though citizens can choose their guild associations, long-standing traditions steer certain individuals toward a particular guild. For example, it would be highly unusual for a Devkarin elf (a dark elf) to join any guild other than the Golgari, and the Ordruun line of minotaurs has provided the Boros armies with generations of offspring. Members of certain races are also drawn to specific guilds, as noted in the description of each of guild.

You establish your character's membership in a guild by choosing that guild's background from among those detailed in this chapter. This book assumes that you have chosen a guild and that you maintain your association with it throughout your life. As a result, your choice of guild can play a more significant role than most backgrounds do in shaping what your character does now, not just what you accomplished in the past.

The backgrounds associated with guilds in this chapter work like those in the Player's Handbook, giving you proficiencies, languages, equipment, and suggested characteristics (personality traits, ideals, bonds, and flaws). Each guild entry also provides personal contacts; suggestions for your alignment, race, and class; and a list of spells that you can add to your spell list if you're a member of a spell casting class.

The spellcasters of Ravnica's guilds have a style of magic specific to their guild. A guild's description includes a list of guild spells that epitomize the type of magic the guild favors. The Boros Legion, for example, tends to prefer using spells of fire magic and holy light, and its guild spell list reflects that emphasis.

If you play a character who has the Spell casting or the Pact Magic class feature, your guild spells are added to the spell list for your class, thereby expanding the spell options available to you.

As a benefit of your guild membership, you have contacts both inside and outside the guild. Contacts are useful resources in the urban environment of Ravnica, where a friendly face can be more valuable than gold.

As stated in the Player's Handbook, bonds represent your connections to people, places, and events in the world. Contacts are people you have a connection to, but they're not necessarily bonds. People can be bonds if they inspire you, motivate you, or make you act against your best interests. (They can represent flaws if their existence amounts to a weakness for you.) Contacts, in comparison, are simply people you know. They might be friends, rivals, or even family members, but their relationship with you is rarely as strong as with a bond.

Although the tables of contacts in this chapter describe non player characters who are members of guilds (your own and others), you are likely to acquire guild-less contacts as well. NPCs such as goblin gang leaders, minotaur bartenders, and vedalken tailors all go about their lives in the shadow of the guilds but divorced from those groups' intrigue and politics.

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