So the final bosses of the Force-sensitive protagonists are Darth Baras, Darth Thanaton, the First Son (with Syo Bakarn resisting) and the weakened Emperor's Voice.
If they all met in the caverns of Corellia and duked it out, who would win?
First Son is comfortably more powerful than Baras to me, but with Syo wrestling him for control I can see your point. Though Syo won't be healing any of his adversaries, this time.
Thanaton's pretty powerful but I've always depicted the weakened Voice as being more powerful. The only one who could properly hold a candle would be the First Son, but with Syo wrestling him mentally, I think Vitiate's Voice could pull it off.
Though this is a free-for-all, so it's hard to tell who would fight who, exactly. I'd expect Vitiate to attack Baras in revenge, whilst the First Son is probably still loyal to Vitiate and would likely fight Thanaton.
Voice probably takes this. I'm curious as to why everyone is saying Thanaton is at the bottom of this. I've always viewed him as stronger (in terms of Baras in final fight and Thanaton final fight). He did say this was final boss fights, IMO Thanaton in his final fight before death > Baras in his final battle before death. Then it's probably First Son under Thanaton for reasons of Syo fighting back mentally.
Thanaton didn't really lose to Nox in Act II, Nox started spazzing out uncontrollably and both of them got shat on by her inability to control her power.
But you're on point that Thanaton got absolutely dominated by Nox with her literally backhanding his attacks while Baras gave a good fight.
I don't have TOR installed right now, but I believe it says something along the lines of you faced Thanaton and defeated him, but now your body is disintegrating.
Don't pay him any attention. Whenever someone challenges Revan's place and he disagree's, Ant always overreacts and starts calling them fodder. He's just immature and petty.