The Riverpaw Advisors (also labeled Grand Advisors) are a group of appointed officials that are responsible directly to Emperor Hogger.
Their purpose is to maintain contact with the High Council and oversee the entire runnings stockings while the Emperor himself is not present and complain about the nerfing of their fireballs.
The true number of Riverpaw Advisors is only known to the Emperor. They are more then two and less then four, it seems. Five is right out. They seem to have few true organization as opposed to the High Council which has a clear established sense of authority over the Silvermoon Empire. This is not ominous at all, no sir. Go about your bisness, citizen.
The Riverpaw Advisors seem to appear whenever the Emperor is not present and relay his instructions to the rest of the Empire, including the High Council. They do this through spamming Trade chat.
The High Council seems helpess to discipline any Riverpaw Advisor but the Advisors are limited to simple observation and relaying of information. They are not permitted to enforce any rules or such. This in effect limits their powers. They are immune to the instructions of the High Council which brings certain intimidation to their presence. Really. This is not a bad idea, seriously.
The Riverpaw advisors are made up of Devias Pillagers who were appointed to the position after their fireballs were nerfed, hard. Once one of the most feared mobs in the land (after Hogger himself) they are now little more then low-key nusances.
Advisors are addressed by the title "Yes, Minister".