Its Simple Nihilus takes them all, due to fact he eats their force and leaves them dead.
Unless the Ancient Sith have a defense against it which is unlikely.
However since Nihilus wins any fight with any force user, i believe he should be banned from being used in further threads.Reason: He'll always win and there is no point in making a thread where you know the victor
Arker, the guy eats the force... He literally destroys it. It probably doesn't matter how powerful people are, he would still eat it. And Ragnos is powerful sure, but he is he more powerful then a planet filled with force sensitives, the planet it self and a shit load of Jedi? In force potential? I seriously doubt anybody is and Nihilus ate just that. Ragnos, Sadow and Kun are nice but they would be eaten too just like everybody else.
Originally posted by Numan
Yes but there is no proof that he would be able to use his ability in a while having to defend himself in a melee duel. So if the trio work well together and have a good strategy, they could probably pull it off.
He tried to eat the Exile while fighting him, he has killed many Jedi that went to confront him, he defeated Kreia and took much of the force from her by a single wave and he once did the same against Sion... There is plenty of prove to show he could use the attack in a heartbeat. Actually everything suggests he can, therefor he can and will.