Raven-shadows suggested this Episode IX Prediction and asked me to write a theory about it.
This is the best Episode IX Theory/ Prediction that I've ever heard!!!
So, if you have read any of my Episode IX predictions, you know that I think that Anakin could be the Skywalker who rises, that he could appear as a Force ghost in Episode IX.
But, me, Raven-shadows, and Winter Wolf were discussing our theories about the trailer.
Especially about Palpatine and rather or not we like the idea of his return. And what we think his role will be in Episode IX.
And then Raven-shadows suggested this idea.

So, I know that some Star Wars fans have the theory that Palpatine created Anakin, and I'm not saying that he didn't, but there was nothing in the movies that confirmed that. And if that was true it would somewhat contradict Anakin being the chosen one. Palpatine only wanted Anakin to bring darkness, not to bring balance.
So if the Force itself created Anakin to bring balance to the Force. Then he was also created to defeat Palpatine, as he is the enemy of balance, trying to destroy all light in the galaxy and leave it only in darkness.
But, if balance is gone and Palpatine survived, did Anakin accomplish what he was created to do?
If the Force is always trying to balance itself out: "darkness rises and light to meet it."
Every time darkness rises, light rises to meet it. The reason Rey is so powerful in the light side is because Kylo Ren is so strong with the dark side. The Force made her strong enough to counter balance him.
Snoke and Luke counter balanced each other, but they are both gone.
But if the darkness rises in the form of Palpatine, will light rise to meet that darkness?
And if it does, who will be that light?
The answer: Anakin Skywalker.
If the Force created him to defeat Palpatine and bring balance to the Force, then who could say that the Force couldn't bring him back to accomplish that task?
And I'm not talking about a Force ghost, I'm talking about Anakin. He was created by the Force, if anyone can be brought back, it's him.
The Rise of Skywalker.
"Darkness rises and light to meet it."
If Anakin returns, then he could fulfill the prophecy and bring balance to the Force. And he could defeat Palpatine once and for all.
Perhaps Palpatine conveniences Ben to join him. Rey and Anakin go to face Palpatine.
I'm imagining Rey fighting Kylo Ren while Anakin fights Palpatine. But then Palpatine hurts Rey, like he did to Luke and it causes Ben to side with Rey and Anakin. Even though, when he realizes that Anakin is grandfather, he might join them immediately.
Of course Palpatine could lie to him and say that Anakin killed his grandfather, Darth Vader, which he did. Which would cause Ben to be against him.
Regardless, Ben would eventually join them and together they fight Palpatine. Ben would be redeemed, and Anakin would finally accomplish what he was created to do!
That would just be the most epic Star Wars movie I have ever seen! It would definitely become my new favorite, and I doubt any future Star Wars movies would ever beat that.

Okay, this theory probably brought my expectations for Episode IX way too high.
I've got to bring my expectations back down from 10 to 1 so that I won't be disappointed.