Star Wars revealed that Yoda received a warning about Order 66 at the start of the Clone Wars, making it unclear why the Jedi Master chose to ignore it. Order 66 wiped out most of the Jedi Order, so if Yoda knew about it in advance, then he could have taken steps to make sure it didn't happen.
Yoda had been completely outplayed by Palpatine, and he knew it. Yoda understood that Order 66 was coming by the end of the Clone Wars, and probably that Palpatine was the Sith Lord, but he could do nothing about it.
Multiple times Yoda is told that a dark future will soon happen, but Luke Skywalker will eventually rise up and defeat the Sith. So, it's likely Yoda didn't want to interfere and alter the future, as he'd be at risk of preventing the Sith from being defeated many years later.
From the secrets of Jango Fett and the Kaminoans to the truth about Dooku and Syfo-Dias, the Jedi had plenty of opportunities to prevent Order 66. The Jedi had plenty of chances to find out the truth about the clone army and prevent Star Wars' Order 66 from happening.
Yoda still stands as one of the most powerful characters in Star Wars, yet even he couldn't defeat Palpatine. After their battle in Revenge of the Sith, Yoda felt beaten and fled into exile on Dagobah, where he hid away for 19 years.
Mace Windu failed in his mission to arrest Palpatine in Star Wars: Episode III - Revenge of the Sith, but Yoda may well have fared better. As powerful as Darth Sidious may have been, it's easy to forget he actually seemed afraid of Master Yoda.
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.
Without Order 66, Palpatine would definitely lose. If Order 66 happened but not for some of the most powerful Jedi and the more battle-hardened and experienced Clones, Palpatine still loses even though many Jedi are killed.
The Sith Would Have Won In The Event Order 66 Failed
In this example, the Jedi would likely have failed to survive the Empire. Thwarting Order 66 would only delay the inevitable. With almost the entire galaxy on his side, it would only be a matter of time until Palpatine wiped out the remaining Jedi.
The order was programmed into the Grand Army clone troopers through behavioral modification biochips implanted in their brains, making it almost impossible for the clones to disobey the command to turn against their Jedi Generals.
Yoda didn't specifically know how this would go down, or to what degree Anakin would cause it to happen, but he was playing a much longer game by Revenge of the Sith, and that's at least, in part, explained by Yoda's Force connection with Qui-Gon's spirit.
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.
It was said that fewer than one hundred Jedi—approximately one percent of the entire Order—survived Order 66. However, the number seemed closer to two hundred.
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.
And it eluded him completely." Although Yoda doesn't know it, he is sensing the concealment of the dark side embodied in Palpatine, the Dark Lord of the Sith.
While Yoda may not be as strong a fighter as other masters, he is probably has the strongest connection to the Force among all. He can sense death and pain even from half the galaxy away, especially among other Jedi.
Presumably Palpatine planned to have Anakin join him at that point and so told the clones not to kill him when he gave out Order 66.
Order 67 was an order requiring clone troopers to dance. During the Battle of Utapau, Darth Sidious accidentally issued Order 67 when he meant to use Order 66. Just after the order was executed, Cody and his troops began dancing. However, Sidious browsed a manual and executed Order 66.
Anakin would have likely been killed by the clone troopers, along with the other Jedi. However, perhaps he would have escaped. He would have taken the pregnant Padme with him. He would have needed to get as far away from the eventual Empire as possible, so perhaps they would have gone with Yoda to Dagobah?
In Legends, the Jedi knew about Order 66. They just didn't know it could be used in the way it was. It was billed to be used for taking down dark Jedi or rogues. Even before the biochip thing, the clones were flash trained with the expanded meaning of the order, which the Jedi were unaware of.
Due to Skirata's influence and support for Darman, Omega Squad refused to follow Order 66. Another clone commando group, Yayax Squad, had a smaller role in the Republic Commando novels, and like Omega Squad, these clones disobeyed Order 66. Cov, the leader of Yayax Squad, was in love with Kal Skirata's daughter.
Yoda Was Warned About Order 66 At The Beginning Of The Clone Wars - But Why Did He Ignore It? Star Wars revealed that Yoda received a warning about Order 66 at the start of the Clone Wars, making it unclear why the Jedi Master chose to ignore it.
This ensured that the Sith could hone their skills in secret without fear of betrayal from rival Sith factions. 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.
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.