|Alternative name|| The Unseen,|
The Tenth Guild
|Guild leader:|| Szadek|
(Ravnica block; deceased)
(Return to Ravnica block)
|Guild champion:|| Circu|
(Return to Ravnica block)
(Ravnica: City of Guilds)
|Featured sets:|| Ravnica: City of Guilds|
|Signet flavor text:|
|"An emblem of a secret guild, the Dimir insignia is only seen by its own members — and the doomed." — Dimir Signet|
House Dimir is one of the ten guilds of Ravnica. It is a guild of secrecy, manipulation and underhanded deals, a shadowy organization operating behind the scenes to twist Ravnica to its own ends.   The guild provides espionage, smuggling, burglary, counter-intelligence, assassination and other illegal services for the Ravnican populace, although its patrons are unaware that they are in fact employing the guild, instead thinking they are employing guildless mercenaries or another guild such as the Rakdos. The guild is so secretive that even its own agents often do not know who they truly work for.
House Dimir was founded by the ancient vampire Szadek. The vampire was one of the ten paruns that signed the Guildpact and remained in charge of the guild for the subsequent 10,000 years. One of the crucial clauses of the Guildpact was that none of the signatories (including Szadek) could reveal the existence of the Dimir to Ravnica's people, protecting the guild's anonymity while forcing it to remain hidden. This created a flaw in the Guildpact's structure that would eventually allow it to be broken.
Officially, the guild does not exist. The Ravnican people generally believe that there are only nine guilds and that if there ever was a tenth, it dissolved thousands of years ago. The name Dimir is not known by most people and those that do know it believe it to be a myth, children's story or a paranoid conspiracy theory. This misinformation is actively propagated by the Dimir themselves as a method for avoiding suspicion.
The guild operates on a strictly need-to-know basis. At the top of its hierarchy is the leader. Only he is fully aware of all of the guild's activities. Beneath him are the necrosages, who oversee the guild's activities from Duskmantle. They manipulate the flow of information, keeping the guild informed on all things whilst keeping the rest of the plane ignorant. Few individuals are ever allowed to meet the guild's leaders, as instead a network of middlemen are employed to pass on messages to cells of field operatives. Agents at the very bottom of the guild only meet a mysterious individual in a back alley that gives them some basic information on their target and nothing else.
The Dimir's guildmages use their magic to influence the minds of others. They can send messages to operatives over distances or strike people with amnesia, magically alter memories or even perform lobotomies on victims to cover their tracks. The Dimir also practice necromancy, creating undead minions such as skeletons and wights to carry out missions. Such minions are employed as they are single-minded, easy to create and dispose of, cannot be interrogated in the event of capture and are easily blamed on the Golgari instead. Spirits are also used by the Dimir to pass on messages, carry out surveillance invisibly or even to possess important figures such as judges and senators. Nobody is beyond the reach of House Dimir.
Szadek as leader of House Dimir is the main antagonist of the Ravnica novel, manipulating Savra and the Selesnya Conclave to do his bidding and kill Mat'Selesnya. He is ultimately defeated when Jarad takes control of the lupus and forces them to attack him. After that, he is arrested by Agrus Kos, and imprisoned by the Azorius who secretly execute him.
After the events of the Dissension novel, a new Guildpact is formed that does not recognize the House Dimir as an official guild. However, the district of Agyrem reappeared within Ravnica, and is under Szadek's (now a spirit) control (he can easily control the other spirits that inhabit it), which means that the guild is still operational and possibly, stronger than ever.
Return to Ravnica block
Although not officially recognized as a guild under Teysa Karlov's non-magical Guildpact, House Dimir is still active under Lazav's leadership. The fact that the general populace now knows of their existence required adopting a public face, so the lower ranking members serve as couriers, investigators, reporters, and archivists.
The true power of the guild still lies in the network of spies, assassins and thieves.
In the game
Ravnica: City of Guilds: Transmute
The Dimir game mechanic is Transmute: it allows a player to pay the transmute cost of a given card, discard it and search his or her library for a card with the same converted mana cost as the discarded card.  
The Dimir game mechanic in Gatecrash is Cipher, which allows a player to encode a cast spell on a creature, casting a copy of it for free each time the creature deals combat damage to an enemy player. Another mechanic frequently appearing on this guild's cards is milling, which allows a player to win the game by removing cards from his or her opponent's library. A special variant of mill called Grind appears on many Dimir cards in the Return to Ravnica block.  While Magic is set up so there is a large amount of hidden information at any given time, there are always ways to use an inequity in that information to your advantage — a specialty of the Dimir. 
Notable Dimir cards are:
- Glimpse the Unthinkable
- Psychic Drain
- Dimir Doppelganger
- Dimir Cutpurse
- Circu, Dimir Lobotomist
- Drift of Phantasms
- Watery Grave
- Dimir Infiltrator
- Duskmantle Seer
Species and races
Species and races associated with House Dimir include:
Classes associated with House Dimir include:
- Matt Cavotta. (November 09, 2005.) "The House That Lies Built", Daily MTG, magicthegathering.com, Wizards of the Coast.
- Magic Arcana. (November 08, 2005.) "Ravnica Style Guide: Dimir", Daily MTG, magicthegathering.com, Wizards of the Coast.
- The Art of Gatecrash
- Planeswalker's Guide to Gatecrash: Part 1
- Mark Rosewater. (November 07, 2005.) "Pretty Sneaky Sis", Daily MTG, magicthegathering.com, Wizards of the Coast.
- Aaron Forsythe. (November 11, 2005.) "Secrets of the Secret Guild", Daily MTG, magicthegathering.com, Wizards of the Coast.
- Mark Rosewater. (March 18, 2013.) "Designing for Dimir", Daily MTG, magicthegathering.com, Wizards of the Coast.
- Sam Stoddard. (March 22, 2013.) "The Nature of Secrecy", Daily MTG, magicthegathering.com, Wizards of the Coast.
- Dimir Dementia, the Gatecrash intro pack
- Dimir Intrigues, the Ravnica: City of Guilds preconstructed theme deck
- Ravnica: City of Guilds: House Dimir Minisite — Wizards of the Coast
- Return to Ravnica: House Dimir Minisite — Wizards of the Coast
- Gatherer watermark search for Dimir, Gatherer — Wizards of the Coast