How could Asajj Ventress be a Sith if there can't be more than two of them?

Question

At the very end of Star Wars, episode 1: The Phantom Menace, Mace Windu and Yoda had this discussion :

Mace Windu: There is no doubt. The mysterious warrior was a Sith.
Yoda: Always two there are.... no more... no less. A master and an apprentice.

Within the movie series, this principle is respected. The only exception I see is Grievous, but I don't think he counts as an apprentice only because he can wield some lightsabers, he does not appear to be a force user which is a major part of the apprentice description.

But in expanded universe, this rule seam the be broken fairly often. One notable example is Asajj Ventress from the Clone Wars animated series. How she (and others) could be a Sith if there is already two of them with Sidious and Dooku?

Answer 1

There are only two Sith, one master and one apprentice. One to embody the power and the other to crave it. This decree came from Darth Bane.

In the case of Asaaj Ventress, she is a dark jedi/ Sith aspirant. Another term is that she is a dark side adept. Ventress is also Dooku's "secret" apprentice. She is Dooku's assassin, not a Sith. Dooku/Darth Tyranus hopes to use her to beat Palpatine/Sidious. Only then could Dooku make Ventress his true apprentice. However, she is no secret as Sidious realizes that Dooku is training her in a future attempt to kill him. Darth Sidious orders Dooku to kill her, but she survives.

I highly recommend Jedi Vs. Sith: The Essential guide to the Force.

Answer 2

The Rule of Two, which Mace Windu and Yoda are talking about in your question, is a rule setup by Darth Bane to consolidate the power of the Sith order and basically make the master stronger. At the same time there is also a push/drive for the apprentice to become the master. If there are only two the stronger of the two, the master or the apprentice, would survive their ultimate confrontation.

This model also was to keep the Sith hidden from the Jedi. The Jedi eventually found that this was happening and why they believe that there are only two at any time.

Also, Dooku most likely thought that she was hidden from his master, but if Sidious, in his eyes, found it to his personal advantage to let Dooku have an apprentice there would be no reason for him to stop it.

It basically comes down to the fact that if the master believes themselves to be superior and they can bend the situation to their benefit then they can let it happen and manipulate the situation.

Also, even in the Darth Bane books at the end Zannah, Bane's apprentice, had just recruited her own apprentice. Although the apprentice was order not to interfere with the battle between master and apprentice.

Answer 3

Technically, Ventress is Count Dooku's apprentice. However, Dooku was Palpatine's apprentice at the time...

A lot of this is covered in The Rule of Two entry on Wookieepedia. TL;DR - Palpatine considered it more like what you'd call "guidelines" than an actual rule, really.

Answer 4

She wasn't a Sith, she was a Dark Jedi. She was never indoctrinated into the ways of the Sith, and therefore did not know their secrets. As long as she did not sport the "Darth" title, it was fine.

Answer 5

I think they took the use of the word Sith rather deliberately to make it easier to draw the lines. Ventress was trained in the Sith arts and would count as Sith apprentice but she's not a true Sithlord as Doku and Palpatine understand themselves. She's not Darth Ventress, because as I understand it only a true Sithlord is given that Title and there are always only two, at least known during that time. If there appears another "Darth" I think the real Sithlords might indulge him/her but a simple title does not yet make you a true Lord unless you beat your predecessor.

Answer 6

Asajj Ventress was not a Sith. From the canon reference book Star Wars: Absolutely Everything You Need to Know:

[Emphasis Theirs']

Q: Is Ventress a Sith?

A: Ventress draws her power from the dark side of the Force and is mentored by Count Dooku, yet she is not fully trained in the ways of the Sith. Her skills are undisciplined and not perfect.

Keep in mind that the Rule of Two was never an enforced law or biological constraint. Dooku likely intended for Ventress to be his apprentice after he overthrew Palpatine, but she was never an official Sith. In fact, Palpatine ordered Dooku to kill her to prevent that from happening. There is no hard limit on the number of Darksiders that can exist at a given time.

Answer 7

Could be a lack of distinction between THE Sith, the two, and the sith being used as a general term for any others (force-wielding or not) who may follow the Sith ways.

Also, there is always also the idea of the original RACE of Sith, the beings, not the ideologues. Perhaps she had actual Sith blood? I don't know enough of her character, but that could be another possibility.

Answer 8

I thought it simply meant that they come in pairs. So there might be hundreds, but they don't group together more than two at a time. Nor are they loners.

Answer 9

Allow me to provide a different (and far more likely) view, because you're all forgetting Mace Windu's line:

Mace Windu : There is no doubt. The mysterious warrior was a Sith.

Yoda : Always two there are....no more...no less. A master and an apprentice.

Up until this point, the Jedi had thought the Sith were gone. But here, they discovered one still around. Yoda was simply noting that a Sith master always had an apprentice (or nearly, he may be between them at the moment..).

This particular line makes no reference to a limit of two Sith, just the knowledge that an unknown Sith was still around.

While I can't say for sure about the expanded universe and the Rule of Two that was established, this line seems to be the basis of the assumption by fans and those authors that there were always only two sith in existence, since it's nearly always referenced... When it just looks like a misunderstanding.