Post Four - The Blitzkrieg
(1) George Lucas, George Lucas and the Cult of Darth Vader
"But Obi-Wan screwed that up by cutting off his arms and legs and burning him up. From then on, he wasn’t as strong as the Emperor – he was like Darth Maul or Count Dooku."
(2) Obi-Wan, Star Wars Labyrinth of Evil
"Clearly Anakin was as strong in the Force as any Jedi who had ever sat on the Council. But as Obi-Wan had told him time and again, the essence of being a Jedi didn't hinge on attaining mastery of the Force, but on attaining mastery over oneself."
(3) Mace Windu, Star Wars Revenge of the Sith adult novelization
"Skywalker is arguably the most powerful Jedi alive, and he is still getting stronger."
(4) Agen Kolar, Star Wars Revenge of the Sith adult novelization
"And even if the prophecy has been misread. Anakin is the one Jedi we can best hope would survive an encounter with a Sith Lord."
(5) Jacen Solo, Star Wars Legacy of the Force - Bloodlines
"'I’m more powerful than any of you.'
It was a boy's expression of anger, but it was true."
(6) Star Wars The Official Figurine Collection #8
Anakin Skywalker was the most powerful Jedi the galaxy had ever known.
(7) Star Wars Miniatures - Ultimate Missions - Revenge of the Sith
Anakin Skywalker is the most powerful Jedi in over a thousand years . . . This makes Anakin, in effect, a Jedi Master, a rank that Anakin, with his unprecedented power in the Force, feels has been long overdue.
(8) Star Wars Dark Lord - The Rise of Darth Vader
Once the most powerful Knight ever known to the Jedi Order, he is now a disciple of the dark side, a lord of the dreaded Sith, and the avenging right hand of the galaxy’s ruthless new Emperor.
(9) The Making of Star Wars Revenge of the Sith
Gillard also reports that the duel will explain how Obi-Wan is able to defeat his protege, even though Anakin has been established as the most powerful Jedi who ever lived. "Obi-Wan taught Anakin and Anakin has gone past him," he notes. "But when you get to that duel, it's emotional. That's where the mistake will be made. And if you know the characters, you know Obi-Wan isn't going to get emotional and he doesn't make mistakes."
(10) Darth Sidious databank, Star Wars official website
As Palpatine, he befriended Skywalker, becoming a close friend and a fatherly authority to a youthful warrior often confused by his seemingly boundless power and abilities he had at his disposal.
(11) Darth Vader databank, Star Wars official website
Skywalker was seduced by the dark side of the Force. His boundless abilities fueled a sense of pride that hastened his fall.
(12) Darth Vader databank, Star Wars official website
Palpatine elevated himself to the position of Emperor, and dispatched Vader as his ultimate enforcer. With his unparalleled Force abilities, Vader swept through the Jedi Temple.