Magnificoes are members of the ruling class, whether that be royal or noble families, a church that holds temporal power in a region, a wealthy merchant, a powerful guildhall, elected officials, or even crime lords. While magnificoes themselves may not rule, they move in the same social circles as those that do, and are accustomed to getting their way by using influence and persuasion...
Magnificoes adventure when doing so gives one something he or she wants, whether that be riches, a specific item, or being able to call oneself a dragon slayer.