The Guilds system at Creeper's Lab consists of a series of quests that can be pursued for rewards and ranks.
For the full, official explanation on how the guilds work, see Twixxi's guide on the forums.
There are six main guilds in Creeper's Lab. Each of these guilds provides their own set quests and rewards.
The monthly goals of each guild can be found on the Monthly Challenges page.
The Guildhalls are a place to partake of challenges involving building, mining, fishing, farming, hunting passive mobs, and crafting. Stop in monthly for the latest, and collect your rewards!
Guildhall Laurasia - Apprentice Rank
Guildhall Laurasia on the Map
Guildhall Rodinia - Journeyman Rank
Guildhall Rodinia on the Map
Guildhall Superia - Expert Rank
Guildhall Superia on the Map
Guildhall Gondwana - Master Rank
Guildhall Gondwana on the Map
The Specialist Tasks are also found within Gondwana's guildhall.