He knows how he fights, he knows Anakin's strengths and weaknesses. And Anakin's key weaknesses are his temper and lack of self-control. So Obi-Wan exploited his familiarity with Anakin's combat style, strengths, and weaknesses, combined with his narrow skill advantage, and was able to win.
Mou Kei is a technique specific to lightsaber combat, one that is often forbidden by Jedi Knights. In Star Wars Legends, Mou Kei was described as a lightsaber move that struck multiple points of contact on an opponent, removing various limbs in the process.
Darth Vader initially seemed to have won, walking away leaving Obi-Wan buried in rubble, but Obi-Wan focused on the Force. His mind went to those he loved - the young Princess Leia and Luke Skywalker. Those thoughts gave him the strength to blast his way out of the rubble using the Force.
Obi-Wan eventually left Anakin to the will of the Force when he realized that he could not kill Anakin because he was still a Jedi, and the Code prevented him from murdering a helpless man.
Though Obi-Wan was often an important ally for Anakin, the young Jedi could never see past his envy, even going far enough to allow himself to believe that his master was having an affair with his wife. In the end, Anakin's own jealousy was his undoing and the reason that he would never surpass his master.
What If Obi Wan Woke Up BEFORE Anakin Skywalker Could Kill Dooku
Who is more powerful, Anakin or Obi-Wan?
Because while Anakin is more powerful, Obi-Wan is more skilled. It's an extremely narrow skill gap, as we can see that they're almost evenly matched for most of the duel on Mustafar - but it's just enough. Also, Obi-Wan taught Anakin. He knows how he fights, he knows Anakin's strengths and weaknesses.
No, just the opposite Vader was considerably more powerful, the reason for his loss on Mustafar was that he didn't have control over his dark side powers yet and his own arrogance undermined his focus.
Obi Wan is one of the most powerful Jedi to have ever lived. He is the best defensive duelist in galactic history according to Mace Windu and numerous factbooks. He had a low sensitivity to the force but mastered it to his fullest potential worshiping the force as opposed to bending it to his will.
Why doesn't Yoda go and fight Vader? Because there were bigger threats. Yoda knew that Sidious was extremely powerful and that Obi-Wan would not be able to fight him. He sent Obi-Wan to Mustafar to defeat Vader instead, as Yoda hoped Vader could be defeated and killed.
Vader did not hunt for Yoda in any cinematic depiction. He and Sidious could not find Yoda as he had exiled himself on the planet Dagobah which had strong dark side energy that masked Yoda's presence in the Force.
Could Obi-Wan have beaten Vader in A New Hope on the Death Star if he really wanted to? Most likely, yes. Obi Wan had already demonstrated that he was a comparable opponent for skill with a light saber on Mustafar where Obi Wan beat Anakin.
Yes, when Darth Vader turned back to Anakin Skywalker and sacrifice himself to save his son, he dies and Obi-Wan uses the force to connect with Anakin's spirit. In that time Anakin apologizes to Obi-Wan, desperately asking him to forgive him for everything he has done to him and everybody over the years.
Yep. Darth Maul didn't really say or show straight up that he "feared" Darth Vader, but he openly stated his belief that he could not defeat Darth Vader without the help of the Jedi, therefore on his own.
Although Star Wars: The Rise of Skywalker concludes with Rey choosing the name of Skywalker and completing her path to becoming a Jedi, it's possible that she was actually the reincarnation of Anakin all along.
A year later, in 4 ABY, with his health rapidly declining, Yoda died of old age when Skywalker returned to see him. He became one with the Force, shortly before Luke redeemed his father Anakin, who fulfilled his destiny as the Chosen One by killing Sidious.
Going by potential power Anakin has 20,000 midichlorians that is known of, but his full potential could have been much higher, maybe 30,000–40,000. Palpatine is stated to have 19,000, so I would safely assume that Rey could have anywhere from 12,000–15,000.
Despite being the Chosen One, Anakin Skywalker was not the most powerful Jedi in Star Wars, as that honor goes to Ahsoka Tano. The Star Wars prequel trilogy focused on Anakin's desire to become the most powerful Jedi, and while he became very strong in the Force, his lust for power drove him to the dark side.
While little is known about Yoda's species, we do know, however, that they're incredibly gifted in the Force. Both Jedi Master Yaddle, and now Grogu, hold great Force powers, but no Jedi Master has ever held greater power than Jedi Master Yoda.
This fell in line with various fan theories and non-canon novelizations that suggested Obi-Wan and Padmé had an affair sometime during the Clone Wars. In the Star Wars prequel movies, Obi-Wan often has a duty to protect Padmé, but there was never any sense of romantic feelings.
Darth Vader did not 'forget' he was Anakin. He believed he was not Anakin Skywalker; a completely different person whom he killed. You will read in EU materials, that he referred to his memories as Anakin, as 'The Jedi'. He suppressed most of Anakin Skywalker's memories - his memories while he was Anakin.
In those movies, Mace was someone who loved confrontation, with his bullish ways usually winning arguments. However, he rubbed many the wrong way, and as the novel detailed, he was someone vehemently against Anakin joining the Jedi Order.
