The Builders' Guild is the group that most of the finest craftsmen in the Realm belong. This can include stone masons, carpenters, metal workers, glass blowers and more. Most Kingdoms have a Builders' Guild house, where you can find the materials used to build that kingdom. The identifier of the Builders' Guild building is the pattern of Fence/Cobblestone Wall/Fence on the building.
The story of the Builder’s Guild dates back to an earlier age, when the Dwarven Clan of Baern Hammerstriker walked through the gates of Port Breigh. Dwarves were rarely seen in cities of men even during the Second Age. Baern dropped his hammer on a small strip of land just inside the bay of Port Breigh and declared the Dwarves were here to make this city undefeatable by the Zombie Pigmen and asked for men to volunteer to learn the building ways of the Dwarves. Men lined up around the city to protect their families from the invading Pigmen.
In 2 weeks time, under the guidance of Baern, the great Walls of Port Breigh were built, and have never fallen since. Many stories are told of seeing Baern late at night speaking words over the stones that men had laid the prior day. Although no one knows what magic he spoke or if it even still functions, the walls look still as new as the day they were built, although that was thousands of years in the past.
Meta
The Builders' Guild building in each kingdom will house the "allowed" blocks with which to build. The Guild building in Port Breigh has every single block in the game laid out in a way to easily see the texture pack and and any changes to all blocks.