Ravnica block
The Ravnica block is comprised of thee sets: Ravnica: City of Guilds (File:Ravnica.gif), Guildpact (File:Guildpact.gif) and Dissension (File:Dissension.gif).
The Ravnica block centered around exploring multicolor cards and concepts in depth, and as such as a spiritual successor to the Invasion block. It was the first block to introduce the "guild model". Where older blocks showed an evolution of the abilities and/or keywords such that the newest set was more advanced (complicated), the guild model contains a number of guilds that are evolved as much as they are going to be, until another block touches on the guilds again.
This block is the first to feature "hybrid mana".
