The Jedi Believed Ventress Was The New Sith Apprentice In Darth Maul: Son of Dathomir, they believed Maul to be Dooku's apprentice, and so when Ventress came into play during the Clone Wars, they assumed the same about her.
Dooku despises Maul for being a threat to him, and for killing his beloved padawan Qui-Gon, and Maul hated Dooku for being his replacement. They also didn't regard each other as a true Sith: Dooku saw Maul as nothing more than a trained animal and Maul saw Dooku as a Sith pretender.
Indeed he did. Dooku (aka Darth Tyrannus) knew his master's identity. At this point the Jedi thought Dooku was the Sith Master. The kidnapping was planned to reinforce public support for Palpatine while further confusing the Jedi about his true identity.
Overall, Dooku was far more equipped to become a Sith Master than Maul was. Had he managed to overthrow Palpatine, Dooku would have been able to use his position, combat abilities, and dark side Force powers to take his place on the throne Palpatine had carved.
In the Star Wars prequel trilogy, the Jedi Order learned that Count Dooku was a Sith Lord in the film "Star Wars: Episode II - Attack of the Clones." The revelation occurred during the course of the movie's events, which were set approximately ten years after the events of "Star Wars: Episode I - The Phantom Menace."
Obi-Wan CONFIRMS Who is More Powerful - Maul or Dooku
Was Dooku a Sith before Maul died?
In Tales of the Jedi, Count Dooku's history is explored a little more thoroughly. According to episode 4, “The Sith Lord,” Dooku was still involved with the Jedi Order during the events of The Phantom Menace, only officially defecting to the Sith shortly after Qui-Gon and Darth Maul's deaths.
Did Palpatine have Maul and Dooku at the same time?
Tales of the Jedi reveals that Dooku and Palpatine were working with each other before Darth Maul was killed. While no longer a Jedi, Dooku had not yet become a Sith.
Sidious revealed to Maul that he did not intend to kill his former apprentice, as he still had use for Maul; it was Sidious' hope that Maul would lead the Sith to Mother Talzin, Maul's mother and the leader of the Nightsisters, so she could be eliminated as a potential threat to the eventual Sith rule of the galaxy.
Maul most likely knew Sidious' double role as Palpatine and Sidious when he served as Palpatine's apprentice. He definitely knew about Palpatine's goal of creating a galactic empire ruled by the Sith. Maul knows that Sidious is the Emperor.
The two were able to free Maul after he had been interrogated by the Sith Lord Count Dooku, and together the three rendezvoused with more Death Watch forces on the moon of Zanbar. Maul took command of his forces once again, and assured them that the war they had longed for was at hand.
It's already been shown in the source material… more than once… that Darth Maul is not on Darth Sidious's level. Every time he dueled Sidious as his apprentice (in Legends) he got easily defeated.
He regretted it because he had essentially wasted 20 years training him. But since he was an enemy at the time of his death on Tatooine, Sid was glad that he did not have to keep watching his back anymore now that the loose ends were tied off.
If the two spared as Jedi, Dooku would probably win the match because he was the better all-around duelist. But if this issue's fight had continued with Windu as a Sith, Windu would have been able to turn the tables.
By Revenge of the Sith, Anakin was considered equal or inferior only to Yoda. Once he became Darth Vader, Anakin had long become superior to Dooku and Mace Windu. He exceeded their power while still living as Anakin Skywalker, and greatly exceeded their power later in life, both in the force and in lightsaber combat.
More than a strategic retreat, Count Dooku running away from Yoda is a reminder that Dooku is far less powerful than Yoda. Dooku could have not beaten Yoda in Geonosis, meaning that the fight would have ended with Dooku either killed or captured had it continued.
Count Dooku's real name, Dooku, was more fitting than his Sith title, Darth Tyranus, as it speaks to his manipulative nature. Dooku played a crucial role in weakening the Jedi and the Republic from within, planting doubt and eroding trust.
