Empire's Wrath speculation
Jedi Master Wyellett and his apprentice Jedi Knight Xerender defeated Darth Baras and took his lightsaber in the Great Galactic War, before becoming much more powerful:
Jedi Master Wyellett was one of the great Jedi heroes of the last war. Deeply concerned with the preservation of life and more interested in communing with the Force than in using his power as a weapon, he nonetheless proved himself in combat time and again. When his apprentice Xerender battled Darth Baras, Wyellett joined Xerender and sought to redeem the Sith; failing, Wyellett seized Baras’s lightsaber and chose to use it as his own, a symbol of darkness brought into the light. Wyellett’s final heroic act was an act of self-sacrifice committed to save his Padawan Xerender and much of the Jedi Council from the legendary Starweird Queen; this resulted in his capture by the Empire. The Imperial starship that was transporting Wyellett was destroyed in the Battle of Hoth, and Master Wyellett has been believed dead all these years. In fact, Wyellett has been in a trance beneath the rubble of the fallen ship, psychically trying to reach out to his former pupil. Now, Wyellett has transcended the concerns of this galaxy and his powers are more realized than ever before.
- Jedi Master Wyellett Codex Entry
During the GGW, Master Wyellett was a peer of Jaric Kaedan, Tol Braga, Syo Bakarn and Satele Shan:
"The lost super weapon Xerender seeks is actually a Jedi Master named Wyellett. Before his capture during the war, Wyellett was among the Jedi's most powerful Masters."
- Darth Baras, Star Wars The Old Republic: Jedi Master On Ice
Jedi Master Wyellett's powers became much stronger after the war and his defeat of Darth Baras:
"Here, I communed with the Force to the expense of all else. It has been a great privilege and quite mind-expanding. The Force is with me, greater than ever now. I suspect that I could defeat you quite handily."
- Master Wyellett, Star Wars The Old Republic: Jedi Master On Ice
The Empire's Wrath defeated Jedi Master Wyellett and his apprentice Jedi Knight Xerender, faster than a cave-in could bury the Wrath:
You have defeated both Jedi Knight Xerender and Jedi Master Wyellett at the crash site and ignored Master Wyellett’s pleas for mercy.
- Star Wars The Old Republic: Jedi Master On Ice
Darth Ekkage, Darth Baras' sister, was one of the greatest Sith Assassins to ever live and could've single-handedly ended the Great Galactic War:
The sister of Darth Baras, Darth Ekkage is one of the greatest Sith assassins to ever live. She and her network of killers were imprisoned on Belsavis after she was betrayed and handed over to the Jedi by one of her own–a Sith assassin who renounced the dark side and sought refuge among the Jedi. Many believe Darth Ekkage was as powerful a weapon as the Sith have ever had, and that their victory over the Republic would have been completed long ago if Ekkage had not been captured. But there are also many within the Sith who fear her–realizing that they could just as easily be her next target.
- Darth Ekkage, Sith Warrior Codex Entry, Star Wars The Old Republic
Darth Ekkage can kill Lord Melicoste with a flick of her wrist:
"I just destroyed a Lord with a mere flick of my wrist, don't blink, I'm about to do it again.
- Darth Ekkage, Star Wars The Old Republic
Darth Ekkage is the greatest foe the Wrath had ever faced, moreso than Master Nomen Karr and Master Wyellett:
"I've never faced a greater foe."
- Empire's Wrath, Star Wars The Old Republic
The Wrath is stronger than Darth Ekkage:
"I am your better. Pretend otherwise. Your heart knows the truth."
- The Wrath, Star Wars The Old Republic
Darth Baras is near-indestructible:
"It is time for you to confront Darth Baras. Even now, Baras is near-indestructible."
- Darth Vowrawn, Star Wars The Old Republic
The Wrath ruins Darth Baras in a fierce duel, despite this:
But to prove such a bold claim to the Dark Council, the Wrath battles Darth Baras in a fierce duel. The Wrath emerges triumphant, striking down the ruined and seething Darth Baras. With vengeance delivered and the Emperor's will satisfied, the Dark Council bows to the unquestionable might of the Emperor's Wrath."
- Star Wars: The Old Republic Encyclopedia
As of the Dread War, the Wrath had become stronger:
"You have grown since Belsavis, in mind and body, in skill and in spirit."
- Dread Masters, Star Wars The Old Republic
The Dread Masters consider the Wrath powerful enough to be their sixth member, a 'Scion of Terror' to make them strong again:
"Our union requires a sixth."
"You were the Emperor's Wrath, you drove a Jedi to the brink of madness and strike terrior into the hearts of millions. Soon you will join us as our 'Scion of Terror', we will feast on your dreams and become strong again."- Dread Master Calphayus & Dread Master Raptus, Star Wars The Old Republic
To be a Dread Master is to be one of the most powerful Sith in the galaxy:
The Dread Masters, terrifying Sith Lords of incalculable power."
- Star Wars: The Old Republic Encyclopedia
The Dread Masters possess incredible, unprecedented power over the dark side of the Force.
- Dread Master Styrak Codex Entry
By the Revanite War, the Empire's Wrath has become the most important Sith in the empire:
"You are of singular importance to our future. The Emperor may have abandoned you, but in my eyes you are ever the Empire's Wrath."
- Darth Marr, Star Wars The Old Republic
Arcann considers the Wrath the most formidable Sith in the galaxy, with Darth Marr stood right behind them:
"You Sith are quite formidable, you most of all."
- Arcann, Star Wars The Old Republic: Knights of the Fallen Empire
What do you think? Is the Wrath actually the most powerful protagonist of all? Debate!