What constitutes as an Yin/Yang/Yinyang element technique?

Question

As we know, the Naruto "Table of the elements" consists of more than just the basic 5.

In addition to all of the combination elements, (Wood, Ice, etc), we also have the three rather bizarre Yin, Yang, and YinYang elements.

What are they? What can they do? Tobi explained that mastery over these elements allows one to basically become God, completely erasing the boundary between dream and reality. However, is that all there is to it?

The Second Mizukage states that genjutsu is basically Yin element, what does that make the Yang element?

Also, what is the YinYang element? Is "God" the only jutsu there?

What about elementless jutsus like Shadow Clone, do they constitute as either of the three?

Answer 1

This will only partly answer your question, but according to naruto wikia ¹,

Yin relates to one's spiritual energy and Yang relates to one's physical energy and it's necessary to utilise both of these in order to mould chakra for ninjutsu.

I thing that the phrase "become God" is used as a metaphor. According to the same wiki, the Sage of the Six Paths had absolute control over Yin and Yang, and was able to "make his fantasies come to life". This is described as ²

The process he used is explained to have initially involved the administration of imagination, and the spiritual energy which forms the basis of Yin chakra to create shape and form from nothingness. Then, through the application of vitality, and the physical energy which forms the basis of Yang chakra, he would breathe life into the prior form.

The Second Mizukage states that genjutsu is basically Yin element, what does that make the Yang element?

Yes, genjitsu is basically a subset of Yin release (Inton, 陰遁). Based on the fact that Yin relates to spirit energy, and Yang relates to physical energy, that makes perfect sense, because genjitsu techniques are basically illusions. According to the wiki again, the Yang release (Yōton, 陽遁) is "based on the physical energy that governs vitality" and ³

can be used to breathe life into form.

It's also the Yang part of the Nine-Tailed Fox's chakra that was sealed within Naruto. This causes the Yang chakra to have impact on other techniques when Naruto is in Nine-Tails Chakra Mode - namely, the Wood Release technique.

It is also implied that the elemental-less techniques, have their source in Yin and Yang (this is from chapter 316):

---

• ¹Yin-Yang Release
• ²Creation of All Things
• ³Yang Release

Answer 2

Yin is spiritual energy and Yang is physical energy. You need to manipulate both spiritual and physical energy to mold jutsus.

In page 11 of chapter 510, Tobi explains that by administering imagination, and the spiritual energy which forms the basis of 'yin' power... he would create shape and form from nothingness. By administering vitality, and the physical energy which forms the basis of 'yang' power... he would breathe life into that form.

Chakra

As you are probably aware, a ninja's chakra is composed of a balanced mix of his spiritual and physical energy. These two components are Yin and Yang, respectively.

On Jutsus

The Yin and Yang nature seem to be the basis for most jutsus that do use nature alteration, but are non-elemental (e.g. genjitsu). It seems that Chakra is formed when combining spiritual and physical energy. Some people are more suited with one over the other, which might determine whether their balance of Yin and Yang naturally leans towards either side. Therefore not all jutsus require an exact balance of these two Yin and Yang. Instead varied proportions of the combined forces by different means based on the intent of the user determine the jitsu.

Inton (Yin Release)

Jutsu like genjutsu and the Yamanaka Clan's psychic jutsu are spiritual and which focus on the mind. So they must use Yin and Yang nature alteration, emphasizing the Yin. These all seem to be jutsu which focus on extending your own chakra to your opponent and connecting your mind (e.g., implanting an illusion) to theirs. Whether it’s to implant an illusion, read their mind, or project thoughts etc. This basically uses spiritual chakra as a manifestation of your mind.

Youton (Yang Release)

Jutsu like Shadow Clones, medical jutsu, and the Akimichi Clan's size jutsu are physical. They focus on manipulating physical substances or creating them from chakra. They must use Yin and Yang nature alteration, emphasizing the Yang.

Summary

Yoton (Yang Release) creates life force. Inton (Yin Release) materializes imagination. Onmyoton/In'youton (Yin-Yang Release) is a combination of both Yinton and Yangton (you could say the Sage of the Six Path's unique application of this is a bloodline ability). It allows one to imagine something and materialize it without giving up anything but chakra. In other words, giving form to one's imagination.

Yin + Yang = Chakra

Yin = Spiritual Energy

Yang = Physical Energy

Yin Release = Uses spiritual energy extending the mind

Yang Release = Uses physical energy extend the body

Yin-Yang Release = Yin Release + Yang Release

Answer 3

• Yin element:
  The yin element techniques, the basis of imagination and spiritual energy, can be used to create form out of nothingness.
  During the Kyuubi attack on Konoha Minato used the Shiki Fuujin to seal the Yin half of the Kyuubi's chakra within the Shinigami.
  It is, as you (and the Second Mizukage) say, the basis of genjutsu.

• Yang element:
  The yang element techniques, the basis of vitality and physical energy, can be used to breathe life into form.
  During the Kyuubi attack on Konoha Minato sealed the Yang half of the Kyuubi's chakra within Naruto.
  Whenever Naruto is in Kyuubi chakra mode, nearby Mokuton technique created trees react to the Yang element's live-giving properties and develop into full-grown mature trees in an instant.

• The Yin-Yang element:
  These are a combination of the use of both elements described above. As Yin is related to the user's spiritual energy and Yang to the user's physical energy, it is necessary to use both of them in order to mold chakra to create Ninjutsu.
  Yamato explains in chapter 316 (page 9) that the manipulation of Yin and Yang is the source of non-elemental techniques such as the Kagemane no Jutsu, Baika no Jutsu, medical ninjutsu, genjutsu, etc.
  The Rikudou Sennin had such a mastery over these that he could use Yin to make his dreams take form and Yang to make his fantasies real.

  Tobi explained that mastery over these elements allows one to basically become God, completely erasing the boundary between dream and reality.

  The Rikudou Sennin's possessed an ability called Banbutsu Souzou (Creation of All Things), with which he created the nine Bijuu, out of the Juubi's chakra. Quoting from the Naruto Wiki:

  The process he used is explained to have initially involved the administration of imagination, and the spiritual energy which forms the basis of Yin chakra to create shape and form from nothingness. Then, through the application of vitality, and the physical energy which forms the basis of Yang chakra, he would breathe life into the prior form. Thus the Sage used this to split the Ten-Tails into nine separate beings.

  The jutsu Izanagi is also derived from this ability.
  Also,

  Madara has implied that Yin–Yang element was involved in the creation of White Zetsu and his clones.

So basically, by mastering these one can become God, since he will be able to put anything that he imagines into life.

And to answer your question regarding Kagebunshin no Jutsu and the like, I'd say that they do come from the mastery of the Yin-Yang element, since they are not produced by any of the basic chakra elements, and they are indeed a product of your imagination come to life.

• EDIT:
  Unlike SingerOfTheFall, I do not think that the "become God" phrase is just a metaphor. As far as we know, the world they live in may be the creation of someone who mastered Yin-Yang elements, thus being able to put the world they have imagined into life (somewhat like what Tobi wants to do with is Tsuki no Me plan (although I believe he needs to do his plan like so because he does not fully master Yin-Yang elements)). I believe that is the kind of power Tobi speaks of when he says "become God".

References:
Elements, Yin, Yang, Yin-Yang and Banbutsu Souzou