Ravnica is a block that consists of three expert-level expansion sets: Ravnica: City of Guilds (October 7, 2005), Guildpact (February 3, 2006), and Dissension (May 5, 2006). Following in the tradition of other Magic blocks, Ravnica takes place in a plane of the multiverse that was previously unexplored in the game's backstory. The world of Ravnica is an ecumenopolis, a vast city that covers the entire surface of its planet, and is home to a diverse assortment of sentient races. Much power in Ravnica is held by the ten "guilds", political factions that each represent a combination of two of . The mythology of Ravnica is loosely derived from Slavic folklore, and the character names reflect this. This plane was revisited in the Return to Ravnica block.