The Ravnica block is the 11th Magic: The Gathering block, comprising of the large expansion Ravnica: City of Guilds () and the two small expansions Guildpact () and Dissension (). The block was released in 2005–2006.
The development codenames for Ravnica block expansions are "Control", "Alt", and "Delete".
Ravnica block fat packs featured specially designed life counters with artwork from the sets instead of the spindown life counters normally found in fat packs.
Thematically, the Ravnica block was multicolor-centered and, thus, was the spiritual successor to the Invasion block of 2000–2001. The Ravnica block was the first block to introduce the "guild model", wherein a number of guilds, each of which with its own cards and abilities and/or keywords, would be as introduced in an expansion and be as developed and complex as they would be (until returning to the plane with Return to Ravnica block), rather than the traditional model of expansions, wherein abilities and/or keywords would be introduced in the first of usually three expansions and then progressively increase in complexity throughout the block. Four guilds (Boros, Dimir, Golgari, Selesnya) were introduced in City of Guilds, three more (Gruul, Izzet, Orzhov) were introduced in Guildpact, and the final three (Azorius, Rakdos, Simic) debuted in Dissension.
The keywords introduced in the Ravnica block are:
In addition to these 10 keywords, the Ravnica block was the first block to feature hybrid mana costs and hybrid cards. Each of Ravnica's 10 guilds featured three hybrid cards, one at each level of rarity as of then; common, uncommon, and rare.
Ravnica block features 11 10-card guild mega cycles, with one card per guild, and one 20-card guild mega cycle (the "imbalanced gold card" cycle) distributed across Ravnica: City of Guilds, Guildpact, and Dissension.
|Off-color activated permanents
||Votary of the Conclave
||Elves of Deep Shadow
|Each of these monocolored permanents has an activated ability that use their guild's other mana symbol. Elves of Deep Shadow is the only spell of this cycle that doesn't have mana as an activation cost.
|Allied boosting spells
||Tin Street Hooligan
||Ribbons of Night
|Each of these mono-colored spells does something extra if you use its guild's other color to pay its mana costs. Those in Ravnica are spells with additional effects, those in Guildpact are creatures that gain enter-the-battlefield abilities, and those in Dissension are creatures with enter-the-battlefield abilities that are sacrificed unless paid for with the other color. 
|Common Hybrid Spells
||Minister of Impediments
||Gaze of the Gorgon
|Each of these common spells has exactly one hybrid mana in its mana cost.
|Each of these uncommon 2/2 creatures costs two hybrid mana of its guild's colors and each has two abilities, each of which requires mana of one of the guild's colors. They form vertical cycle with common and rare hybrid spells.
|Rare Hybrid Spells
||Shadow of Doubt
||Avatar of Discord
|Each of these rare spells has at least two hybrid mana in its mana cost.
|Common Gold Cards
||Plumes of Peace (or Azorius First-Wing, or Overrule)
||Perplex (or Dimir Infiltrator)
||Scab-Clan Mauler (or Burning-Tree Bloodscale)
||Guardian of Vitu-Ghazi
||Leap of Flame
||Rally the Righteous
|Each of these common gold cards uses the guild's ability. Dimir and Gruul have two such cards.
|Unbalanced Gold Cards
||Clutch of the Undercity
||Anthem of Rakdos
||Congregation at Dawn
||Souls of the Faultless
||Drooling Groodion (or Woodwraith Corrupter)
||Invoke the Firemind
|Each of these cards are one of 2 gold cards for every guild (Golgari has 3 cards) that have 2 of one color and only 1 of the other, with rarity varying.
||Isperia the Inscrutable
||Circu, Dimir Lobotomist
||Lyzolda, the Blood Witch
||Ulasht, the Hate Seed
||Teysa, Orzhov Scion
||Tibor and Lumia
||Savra, Queen of the Golgari
||Agrus Kos, Wojek Veteran
|Each of these legendary multicolor creatures rewarded players for playing with cards of their two colors, often doubly so for using multicolor cards. Isperia and Kraj are different, but this is clearly the result of their effects and cost having been swapped with those of their respective guildmaster at some point.
||Grand Arbiter Augustin IV
||Szadek, Lord of Secrets
||Rakdos the Defiler
||Chorus of the Conclave
||Ghost Council of Orzhova
||Niv-Mizzet, the Firemind
||Sisters of Stone Death
||Razia, Boros Archangel
||Momir Vig, Simic Visionary
|These legendary multicolor creatures, almost all of which cost a certain amount of colorless mana plus two mana each of their respective colors, produced powerful effects thematically tied to their respective colors.
|Each of these common artifacts has ", : Add (one mana each of the respective guild's color)."
||Gruul War Plow
||Crown of Convergence
|Each of these rare artifacts have an activated ability costing both of its guild color.
||Golgari Rot Farm
||Simic Growth Chamber
|When each of these common nonbasic dual lands enters the battlefield tapped, its controller returns a land he or she controls to its owner's hand. Each of these lands can tap to produce two mana, one of each of the its associate guild's colors. Each card's artwork was illustrated by John Avon.
||Prahv, Spires of Order
||Duskmantle, House of Shadow
||Rix Maadi, Dungeon Palace
||Skarrg, the Rage Pits
||Vitu-Ghazi, the City-Tree
||Orzhova, the Church of Deals
||Nivix, Aerie of the Firemind
||Svogthos, the Restless Tomb
||Sunhome, Fortress of the Legion
||Novijen, Heart of Progress
|Each of these uncommon nonbasic dual lands taps for and has an activated ability costing mana of the associated guild's colors for a thematically related effect. Each card (all illustrated by Martina Pilcerova) represents the associated guild's headquarters within Ravnica.
|Each of these rare nonbasic dual lands has two basic land types and enter the battlefield tapped unless its controller pays 2 life. Each card's artwork was illustrated by Rob Alexander.
- ↑ Mark Rosewater (June 17, 2013). "Modern Tales, Part 1". magicthegathering.com. Wizards of the Coast.
- ↑ Mark Rosewater (August 27, 2018). "Founding The City". magicthegathering.com. Wizards of the Coast.
- ↑ Wizards of the Coast (December 16, 2004). "Ravnica Revealed". magicthegathering.com. Wizards of the Coast.
- ↑ Matt Cavotta (May 24, 2006). "Hellbent, Hellbent for Threshold!". magicthegathering.com. Wizards of the Coast.
- ↑ Mark Rosewater (May 2, 2016). "Storm Scale: Ravnica and Return to Ravnica". magicthegathering.com. Wizards of the Coast.
- ↑ Mark Rosewater (January 16, 2006). "Just The Ten of Us". magicthegathering.com. Wizards of the Coast.
- ↑ Aaron Forsythe (November 04, 2005). "Reinforcing the Structure". magicthegathering.com. Wizards of the Coast.
- ↑ Aaron Forsythe (April 21, 2006). "Dissension ’s Enhancements". magicthegathering.com. Wizards of the Coast.