Super Saiyan 9 makes the hair in the middle gold while the hair on the sides are gray and the tail color is also gray. It also makes the user hair a little longer and the tail of the user also becomes longer, the fur color becomes blueish green. The eyes of the user turns gray and the skin of the user becomes a little lighter.
Usage & Power
Super Saiyan 9 multiplies the base form by 1,024,000x it's normal amount, this makes it a little hard for Goku as a Super Saiyan 9 to defeat Gohan as a Super Saiyan 8. However, being a Super Saiyan 9 does have its advantages. Since a Super Saiyan 9, like other forms before and after this form. Can use moves from other transformations, plus moves only this form can handle.
This means that the Saiyan's moves are even more damaging, for example. When Goku transformed into this form, Goku gained a new move called Eternal Solar Kamehameha. Which is an enormously powerful, orange-colored Kamehameha wave that uses some of the the power of the Sun's energy.
Plus Goku's own energy, to create a very powerful blast that can cause enormous damage to the opponent. This was how Goku defeated his own son, when Gohan was distracted. Goku punched him in the back, then charged up using the Sun as his source of energy. He then knocked Gohan out with the blast, this blast was considered minor. Since it only knocked Gohan out, when in reality. If Goku used all of his energy, Gohan and much of the city would've been destroyed.
- Goku and Vegeta achieve Super Saiyan 9 while fighting two Wish-Making Dragons (Shenron and Porunga). Who was under the influence of Babidi's magic, which turned them into Majin's. It's important to note that Super Saiyan 8 has a similar control and perhaps Babidi's magic influenced the transformations of Gohan, Goku, and Vegeta.