Revenge of the Sith (2005) Anakin gives in to his hatred of Dooku and uses his anger to overpower him, severing both of Dooku's hands and leaving him helpless.
Palpatine, pretending to be a helpless bystander, goads his future apprentice on. “Do it!” he hisses. Skywalker does, beheading Dooku as he gives in to his base emotions. He almost immediately feels regret, but Palpatine works to dismiss it.
Dooku had very little respect for the young Jedi Knight, despite his bravery and unbelievably strong connection to the Force. Meanwhile, Anakin developed a grudge against the ex-Jedi Master/Sith Lord for cutting off his right arm.
The first being that he was almost certainly harboring feelings of hatred and revenge against Dooku for cutting of his arm and blasting him with force lightning. Secondly he already had a taste of the power that can often come from killing during good rampage against the sand people.
Dooku Didn't Believe Anakin Skywalker Was The Chosen One
You are a worthy adversary. I cannot say the same about your young apprentice." In the Revenge of the Sith novelization, Dooku wanted to recruit Obi-Wan instead of Anakin.
Once a Jedi -- trained by Yoda -- he became disillusioned with the Jedi Order and thirsted for greater power. Dooku voluntarily left the light side behind and became Darth Sidious' dark side disciple, taking the secret name Darth Tyranus and leading the Separatist army.
In legends, Dooku actually explains why he hates Anakin: He could feel Yoda's touch still lingering on the edges like a distant echo. Vividly his mind went back to their last meeting, on Geonosis: swords drawn at last, and finally equal.
Count Dooku became a Sith because the Jedi served a corrupt Republic, but he had another more personal reason to betray the order. The following contains spoilers from Yoda #4, on sale now from Marvel Comics. Darth Sidious was Star Wars' master schemer.
When Dooku was still with the Jedi Order, he was considered to be one of the greatest (if not the greatest) lightsaber duelists of his generation. Anakin really wasn't as good of a duelist as many people hype him up to be.
With a potential Jedi Code-defying love affair with another Jedi, Dooku is more of a foil to his Clone Wars-era enemies, Anakin Skywalker and Obi-Wan Kenobi, with Dooku's lover, Jedi Master Jocasta Nu, possibly retaining feelings for Dooku well after he joined the ranks of the Lost Twenty.
It's not even up for debate that Darth Vader is stronger than Count Dooku. Even before he was at full power, Anakin Skywalker was able to overpower Dooku simply based on his lightsaber training. Had Dooku fought Darth Vader at full power, the fight likely would have been a lot shorter.
Mechno-arms were cybernetic replacements to hands and arms lost in a variety of situations, but more often than not by lightsaber blades. After Count Dooku severed the right arm of Anakin Skywalker in the opening battle of the Clone War, a mechno-arm was grafted to what was left.
It's not shown, but it is clearly insinuated that Anakin killed the younglings. This is confirmed later in the movie when Obi-Wan informs Padme that Anakin killed them. Both are torn apart with hurt and confusion, trying to make sense of something so terrible. How could Anakin do such a thing?
The Younglings Reminded Anakin of How Different He Was
Those negative emotions also power the dark side, meaning Anakin likely felt stronger as he killed the younglings. That, in turn, reinforced his belief that only the dark side could save Padmé.
Giving in to his feelings, Anakin cuts off Mace Windu's hand, giving Palpatine the opportunity to kill him. Anakin regrets this almost instantly, but the thought of Padme was stronger than his remorse This is the moment Anakin officially became Darth Vader and led to serious issues in the Skywalker Saga.
While Dooku was certainly evil -- and even had a Darth sobriquet, Tyranus, that he rarely used -- he was never quite a Sith, at least not in the true sense. Unlike those who espoused the Sith doctrine, Dooku wasn't motivated by hatred or fear, but by the same purpose that drove him as a Jedi.
He fell under the influence of Supreme Chancellor Palpatine of Naboo, and left the Jedi Order. After learning that Palpatine was secretly the Sith Lord Darth Sidious, Dooku turned to the dark side and became a Dark Lord of the Sith himself, replacing Darth Maul as Sidious's second apprentice.
Bottom line, Dooku never considered himself a Sith. And he wasn't; he was a man looking to change the galaxy in a way the Jedi were unwilling to try. And that is why he joined the Sith and became Darth Sidious' apprentice, Darth Tyrannus. When Dooku became Sidious's apprentice, he was already an elderly man.
Count Dooku was once Yoda's padawan learner. He was given the title Jedi Knight and then Jedi Master, and while he was a Jedi Master, he trained his own padawan learner, Qui Gon Jinn.
While Yoda holds his own in both of these fights, he doesn't win any of them. We never see the greatest of Jedi win a fight. They both end in draws. It makes sense that he'd battle to a draw with Darth Sidious, but he should've easily been able to handle his old apprentice Count Dooku.
Dooku was powerful and extremely skillful with his lightsaber, to the point he easily beat Anakin and Obi-Wan. Still, Dooku was less powerful than both of his masters – Darth Sidious and Yoda.
Anakin Skywalker ultimately ended up hating Obi-Wan Kenobi for many misguided reasons, but Darth Vader's subconscious response to the Jedi's final declaration of love in the Star Wars prequels shows the real reason he could never forgive him.
Anakin admits to Obi-Wan that he has been arrogant and unappreciative of his training, and apologizes to his master.
In Attack of the Clones, Obi-Wan became scared of Anakin's destructive potential, claiming that Anakin would be the death of him. In the flashback in Obi-Wan Kenobi, the protagonist was concerned for Anakin's need for victory, which had seen him defy Obi-Wan's guidance.