In Game of Thrones, there were a lot of positions of power, but one of the most overlooked roles was the Master of Whisperers. This individual was responsible for knowing all of the secrets worth knowing and reporting them to the king to help them rule better. Over the course of the series, two characters held this position.
Varys was Master of Whisperers under Robert Baratheon until he fled following the death of Tywin Lannister. In his place, Qyburn stepped into the role and served Cersei Lannister. Each man has his own talents with the job, but who was the best?
Varys: His Little Birds
Many people were left wondering how Varys was able to know all of the things that he knew. He would often speak about his "little birds" telling him all these things and it almost seemed magical. In actuality, Varys was just a very clever man.
He was able to establish a network of spies all across the world who report to him. He even used little children frequently as they would be overlooked by most people and not seen as a threat.
Qyburn: Taking Over
While Varys was able to keep the secret of his little birds hidden for quite some time, it certainly didn't take Qyburn very long to figure it out. It is never shown how he came across this information, but he managed to turn the little children into his own personal informants.
Even though Varys built the whole operation himself, it is perhaps even more impressive that Qyburn was able to outsmart Varys and take it over as he did.
Varys: Across The Narrow Sea
There are more than enough plots and schemes happening in King's Landing to keep the Master of Whisperers busy, but what about the rest of the world? Varys seemed to have no problem finding valuable information anywhere — even outside of Westeros.
Quite impressively, Varys manages to stay up to date on all matters of importance across the Narrow Sea. He is able to bring news that Daenerys Targaryen married Khal Drogo as well as the news when she became pregnant and later hatched dragons.
Qyburn: Secrets Of King's Landing
Qyburn is never shown to have quite as long of a reach with his "little birds" as Varys does. In fact, most of his secrets seem to be relegated to King's Landing. However, his focus does allow him to uncover a very significant secret that very few people knew about.
When Cersei is about to be on trial by the High Sparrow, Qyburn is able to discover that there are endless caches of wildfire hidden all over King's Landing. With this knowledge, Cersei is able to destroy her enemies and take the throne for herself.
Varys: Withholding
There is a distinct difference between how Varys and Qyburn operated as the Master of Whisperers. While Qyburn was staunchly loyal to Cersei above anyone else, Varys's loyalty was never so solid. He ended up serving several different rulers over the course of the series which means the information he gave the king would depend on how he felt about that specific king.
It could be that Varys did know about the wildfire but didn't trust any of the kings with that knowledge. He also didn't tell them about the hidden ages in the Red Keep, which allowed him to sneak around as he liked.
Qyburn: Powerful Allies
When Qyburn is first introduced, he is a disgraced Maester. Through a series of events, he finds himself traveling to King's Landing with Jaime Lannister, which is where he meets Cersei and becomes her most trusted advisor.
This is a very quick rise to power and Qyburn seems to realize the benefits of having such important allies. He knows Cersei wouldn't care about his past crimes so long as he helped her. So, his whole role as Master of Whisperers is trying to keep Cersei in power, thus keeping himself in power.
Varys: Political Moves
Qyburn might be clever enough in choosing the right allies, but Varys is a true political strategist who is making big plays behind the scenes. Even as he is serving Robert Baratheon, Varys is working to get Viserys Targaryen on the Iron Throne.
He even smuggles political allies from Essos over to King's Landing to have secret conspiracy conversations. He eventually manages to help stage Daenerys' successful campaign for the throne, even if it does get him killed in the process.
Qyburn: Loyal Followers
When Qyburn meets with the "little birds" Varys used to work with, he is quite effective in gaining their loyalty through kind words and sweets. However, he eventually shows that they are willing to do more for him than Varys.
During the plot to put Cersei on the throne, Qyburn confronts Grand Maester Pycelle and has his little birds murder the old man. Not only did he convince the network of spies to follow him, but he turned them into assassins as well.
Varys: The Right Reasons
When Ned Stark arrives in King's Landing, he does not know who to trust. Everyone seems to be looking out for themselves and have their own agendas. Varys is also shown to be concerned with his own well-being, but his motivations may be the noblest of any character on the show.
Varys tells Ned that he does not serve a king but rather serves "the realm." All of his secrets and political moves are done to ensure that there is a good leader sitting on the throne who will look out for the people of Westeros.
Qyburn: Knowledge Is Power
Qyburn seems like a kind old man, but his motivations are never as good-hearted as Varys'. Qyburn knows that his role as Master of Whisperers gives him more information than most people in Westeros and he knows how to use that knowledge for power.
He is like the little devil whispering in Cersei's ear about all the ways she can further extend her own power and destroy her enemies.