Guildpact is the thirty-seventh Magic expansion and was released February 5, 2006 as the second set in the Ravnica block. The prerelease was on January 21, 2006.
Guildpact contains 165 black-bordered cards (55 rare, 55 uncommon, and 55 commons). Its expansion symbol is wrought-iron design with three “branches” meant to evoke the three-guild nature of the set as well as the urban theme. Guildpact expanded on the Ravnica block themes of multicolor and hybrid, adding three new guilds to the environment: the Orzhov Syndicate (white/black), the Izzet League (blue/red) and the Gruul Clans (red/green). The set also included the first creatures with exactly four colors, the Nephilim.