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
What happened in Yoda and Sidious' duel that made it so Yoda lost? Yoda lost the fight before it even began. By all means they were evenly matched. It could be argued Yoda was the superior duelist.
More cunning and devious than all but the most attuned Force-sensitive beings, Darth Bane could more than likely defeat Yoda in a battle of both strength and wit.
That was until Master Plo Koon showed up though, and actually managed to defeat Yoda without even using his Electric Judgement ability. Yoda was impressed with Master Plo and gave him great respect from that moment onwards. You can only imagine the reaction of the Padawans watching the fight!
Jedi Master Yoda is the most powerful of them all. This should come as no surprise, as he was the head of the Jedi Order in the prequels and was revered for his abilities during the original trilogy. Yoda's power is unmatched and was a real threat to Darth Vader and the Imperials.
Yoda's Lightsaber Form Hints He Was Vulnerable To The Dark Side - IMDb. With the various forms of lightsaber combat in the Star Wars universe, the form that Master Yoda employs suggests of a possible weakness to the dark side's sway.
Yoda will most likely win in a fight against Darth Vader because he is more skilled with a lightsaber and has the experience and feats that allow him to trim whatever size and strength advantage Darth Vader has over him. In fact, Yoda nearly defeated Palpatine, something that Vader could never do.
In Dark Horse's Star Wars Infinities comic, Darth Vader managed to find and battle Jedi Master Yoda in an alternate Star Wars timeline. While Darth Vader and Jedi Master Yoda never fought in the official Star Wars canon, an alternate timeline from Dark Horse Comics pitted them together with a rather unexpected ending.
Yoda found himself overpowered in battle against Darth Sidious, who would become Emperor Palpatine, but his wise retreat gave him time to mentor a new hope before ultimately succumbing to old age and passing into the Living Force on the planet Dagobah.
As powerful as Darth Sidious may have been, it's easy to forget he actually seemed afraid of Master Yoda.
One of the main reasons why Yoda would've won against Anakin is simply because he was far better trained than him. Yoda could see the moves his opponents were going to make before they made them; therefore, battling against Anakin would've put him at a far heavier advantage.
Yoda was a legendary member of the Jedi Council as a Grand Master of the Jedi Order and member of a mysterious species capable of living for centuries. He was stronger than most in a connection to the Force and though he was small in size, he'd been so powerful and wise having had trained Jedi for several centuries.
Master Yoda has risen above all others to claim the top spot as the most powerful Jedi of all time and the true chosen one according to IGN's audience. He won pretty handily as well, as he was victorious in 89,756 of his 95,243 battles and had a win percentage of 94.2%.
Infil'a put up a fierce fight against Vader, almost killing him by throwing the already damaged Sith Lord off of a cliff. Despite severe damage to his suit, Vader survived the fall, and repaired himself with parts from Infil'a's droid, Arex.
Jedi Battlemaster Cin Drallig and Grand Master Yoda had knowledge and mastery of all seven forms, including Juyo, befitting Drallig's role as lightsaber combat instructor at the Jedi Temple and Yoda's reputation of having mastered all forms of lightsaber combat as did Anoon Bondara, another lightsaber instructor.
Ultimately, Yoda gained a new understanding of true selflessness and of the Force, came to realize his hubris and the mistake the Jedi Order committed by becoming warriors, and unlocked the secret of Force immortality. As the Clone Wars raged on, Anakin and Obi-Wan had become heroes of the Republic.
The Priestesses represented the connection between the Living Force and the Cosmic Force. They existed in the Wellspring of Life, the Force planet, and are mysterious beings who held the key to becoming a Force Spirit. Their relationship to the Force is what ultimately pushes them to be more powerful than Yoda.
Yoda likely would recognize that Palpatine should have died, but that could have come later. If Anakin had arrived when Yoda and Mace had beaten or were about to defeat Palpatine, Yoda would be wise enough to recognize the fragile state of the young Jedi and adhere to his pleas to arrest Palpatine rather than kill him.
Master Yoda failed Anakin Skywalker in Star Wars: Episode II — Attack of the Clones, and it resulted in the destruction of the Jedi Order. Master Yoda is one of the most revered characters in the Star Wars universe, and for good reason, but he ultimately failed in stopping the rise of the Sith.