The ritual was performed to create an enormous nexus of the dark side on Medriaas. Vitiate was the only participant who successfully utilized this nexus for personal gains; the nexus provided Vitiate the opportunity to consume the entire biota of Medriaas.
Legend, Vitiate's drain was indeed the most potent one. Vitiate had more destructive results in Natemha than Nihilus did in Katarr. However, you gotta admit that Nihilus got those results with less effort and his drain is surely more combat applicable.
He isn't arguably the most powerful master of the Dark Side - not even Sidious is.
What's another determinant is the ability to do so whilst under the strain of combat, especially with another person attacking you at the same time that you're trying to Drain somebody else. As you said, no rocket science here. I hope you understand that I don't intend to claim that Vitiate simply cannot perform Drain, but that he would only do it in morals off because his entire history of combat does not involve Drain, and secondly, even if he did perform it here, it would be a fairly rare basis.
I've paid far more attention than you in this debate, LOL. I've read everything you've posted, whereas you've clearly failed to give me the same courtesy, because if you bothered to read my posts comprehensively, you'd realize that I said that even "a limited time" is sufficient to repel an attempt from Vitiate, who would not simply try to rinse and repeat the procedure. And it's ample time for Kun to retaliate with Blasts, which would fairly difficult for Vitiate to counter.
I know all of this - I don't know why you're repeating yourself. You do realize that all the examples of Vitiate siphoning strength from others involved beings too weak to resist (Revan, who could only resist mentally) or people who literally allowed Vitiate to siphon them, like his Servants. None of these happened under the strain of combat, and none of them were against people who actually were in any position to defend themselves. Doesn't work this way - that's like saying Bane can deflect a torrential rainstorm whilst dueling Darth Zannah because he's shown it before, even if it's not in a combative situation.
That's not how it works at all. Bane is also more powerful than Draagh and knows Drain, but he couldn't use it on short notice without amps.
I love how you speak of Vitiate as multiple people.
That being said, Vitiate's "dark and sinister techniques" largely revolve around rituals, and he hasn't displayed any of this stuff in combat. Illusions, Barrier, TP, Lightning and TK are just about everything he's shown in a fight, none of which are beyond Kun or Ulic's comprehension.
And I've already voiced that Vitiate can potentially win, lol.
I'm aware of all this - Naga Sadow knew every single power ever demonstrated in TotJ, Jedi or Sith, plus numerous more hidden in vaults and holocrons/scrolls. His knowledge includes powers the Jedi have never seen and can't withstand. Ragnos logically holds a comparable amount of knowledge.
Kun sensed Ulic as a peer, so yes, here's a peer, to some degree.
Not the novel Vitiate, who studied them and had genuine concern about them. Moreover, among Scourge's numerous visions, Vitiate was slain, it was just that there was an equal chance where Vitiate slew them.
Nope, I knew this already, and I mentioned it, too. You didn't bother to notice it earlier, though. Try to keep up.
1. What implies he's the most powerful of the era including Ragnos and Sadow? Numerous sources suggest that Ragnos and Sadow were the most powerful of their time, so this would be a major retcon which I doubt it is. Vitiate only became more powerful following the ritual on Medriaas, and after the events of the novel where he increased in power to become the most powerful character up to and of his time barring the Ones. And even then, he feared Sadow and Ragnos's spirits, so suggesting that he was more powerful than them before receiving that dramatic increase in power is stretching considerably in my opinion.
2. Right, except he dominates most via rituals or tricks, not combat. He rarely engages in combat to begin with, because of his supreme status (therefore few would challenge him), and numerous examples involve him being able to prepare beforehand and perform some sort of ritual. Ulic, on the other hand, has actually fought in physical/blade combat all his life. Vitiate's fights virtually never involve physical strength or lightsaber skill - he usually manages to win through straight Force power. So how he is tested in combat is different to how Ulic is tested in combat - and as I said, Vitiate's power could be sufficient to overwhelm the duo, but you're being seriously ignorant if you suggest that the reverse isn't a possibility. And yes, I'm aware you said it could happen, but for a minority - I'm just not sold on that, yet, since Vitiate considers the ancient Sith alone to be a threat to his power - and Kun is more powerful than any of them, or at least equal.
He was "tested" by legions, but most weren't defeated in strictly personal combat. He dominated most of those via rituals.
__________________ "Vader's pulse and breathing were machine-regulated, so they could not quicken; but something in his chest became more electric around his meetings with the Emperor; he could not say how. A feeling of fullness, of power, of dark and demon mastery -- of secret lusts, unrestrained passion, wild submission -- all these things were in Vader's heart as he neared his Emperor. These things and more."