Ravnica is a planet covered every inch in city, from the tall spires to the deep sewers, with little room left for nature. The city is split up into factions, each faction controlled by a guild. Each expansion in the block covered a few of those guilds, each of whom represent two colo rs of mana. The plot centers around the Guildpact, a truce between each of the guilds for peace and prosperity, and machinations of some people to stop it from being renewed. Ravnica expands on the themes of multicolor interactions, and even introduces hybrid mana; mana that can be paid by one of two colors. Each guild has a similar layout of cards, including in each of them:
- A legendary leader
- A legendary champion
- A mana-producing signet artifact
- A land that bounces a land and comes into play tapped, but produces two mana, one of each guild color.
- A colorless land with a guild ability
- A two-color land that comes into play tapped unless you pay two life
- A rare guild artifact
- A hybrid-mana guildmage
Ravnica - The first set in the block, Ravnica introduces the setting and the first set of guilds. Each guild has two colors of mana, a flavor and theme, and a mechanic all their own. Ravnica's guilds are: The Boros, a red/white military soldier guild, police and peacekeepers. Their mechanic is Radiance, which allows a spell to target one creature and all others that share a color with it. The Golgari, a black-green guild that focuses on recycling, rebirth, and death as an essential part of life. Their mechanic, Dredge, allows a card to be returned from graveyard to hand, at the cost of milling cards. The Selesnya are green-white monks who believe in the greater good, reflected in their mechanic, Convoke. Convoke allows you to tap creatures in place of tapping lands to reduce the mana cost of large spells. Finally, the Dimir House, a blue-black guild of information, secrets, and espionage. Dimir's mechanic is Transmute, which allows you to pay a cost and search your library for a card with the same cost, playing it instead. It's symbol is a ravnican tower.
Guildpact - Second in the block, it debuts three more guilds. The Orzhov, which are black-white and deal with finance and business... as well as the trading of lives. Their mechanic is Haunt, where a card haunts another, and it's effects are triggered when the haunted permanent dies. The Izzet are blue-red, mad scientists run by a wise and slightly off dragon, who deal in keeping the city alive with technology. Thier spells have Replicate, a cost that can be paid to copy the spell as many time as tthe player wants. Third is the red-green Gruul, barbarians and berserkers whose ability, Bloodthirst, makes their creatures bigger if the opponent was dealt damage that turn. It's symbol is the seal of the guildpact.
Dissension - Debuting the last three guilds, this set is the 60th set printed. The guilds are the Azorius, a blue-white guild built around flying and maintaining the status quo, with their ability, Forecast. Forecast is a cost that, when paid during the upkeep, reveals the card and plays a lesser effect of the spell. The Rakdos cult is run by the demon Rakdos and is black-red, focusing on destruction with their mechanic, Hellbent, which makes their spells more powerful if you have no cards in hand. The final guild is the bio-experimentalist Simic, blue-green masters of life. Thier ability, Graft, is basically modular, except it allows you to move the counters when new creatures come into play instead of when that creature dies. It's set symbol is the guildpact seal, broken.