The Hall of Faces lies hidden deep within the shadows of the Duskmantle, an enigmatic and forbidden space known only to the highest echelons of the Dimir Guild. A place of secrets and eerie stillness, it is where Lazav, the Guild Master of the House Dimir, conducts his most secretive operations. The chamber is a dark, somber hall, its walls lined with countless lifelike masks—faces of the fallen, the traitors, and those who have been erased from the guild's history. These "faces", made from both flesh and porcelain, are meticulously arranged, some depicting former guild operatives, others twisted and unrecognizable.

At the heart of the hall lies a single, ancient stone pedestal, where Lazav often stands, his form shifting with his many faces. It is said that those who venture too close to the pedestal are marked by the masks, becoming part of the guild’s vast network of secrets and lies—an inescapable part of the guild’s dark tapestry.

Lazav is the current guildmaster of House Dimir on Ravnica.
Apart from him being a mindmage and a shapeshifter, details about Lazav are scarce. He (or she, or they) claims to take orders from some greater power. Lazav has a regal bearing and wears a flowing leather cloak, made from the hide of some beast that had gone extinct ages ago. He can warp reality and seems to attract all of the magic in his surroundings toward him.
Lazav's flickering cloak of illusion makes him appear as a blurred, shifting humanoid figure with an ever-changing arrangement of clothes and features. His voice is made harsh and anonymous by a strange buzz, as though heard on the other side of a thick wall.

After Szadek was killed and gained control over Agyrem, Lazav managed to gather what was left of the Dimir and bring them together. A ritual was supposed to allow them to commune with the previous guildmaster's spirit, however, it is unknown whether that was true or just a ruse. Since the Dimir guildhall was lost to all, they built a new Duskmantle, which replaced the old structure. Lazav continued to use most of Szadek's methods, giving both their agents and mercenaries (one of whom is Krenko) as little information as is required to further their goals.
Lazav suspected that an invader had taken over several guilds, and was actively working against them. He discovered that Bolas represented a direct threat to House Dimir's existence by rendering all its scheming obsolete. Although his greatest wish was to mount a coup and seize power over Ravnica, his greatest fear was that he would have to settle for preventing one.
The shapeshifter cleansed his guild of the agents of Bolas. Afterward, he attended the guild summit where he pledged his guild to the alliance that planned to oppose Bolas.
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