forms that go along with Dragon Ball Z

Super Saiyan:
This is the first transformation that Saiyans in this series can reach. It is reached during moments of great emotion or during training sessions. It is also the most often used form among Saiyans. A form which was once one only achieved every one thousand years that has now been reduced to a plaything for the Saiyans of today. There are also some variations of this transformation such as Ascended Super Saiyan (Gold Hair) and Full Power Super Saiyan.
Users: Bardock, Future Goten, Future Saiyaman, Goku, Vegeta, and Vegeta Jr.
Fused Users: Future Vegetrunks, Gotenks,  and Vegetrunks
Defunct Users: Gohan and Roger

Super Saiyan 2:
This form is also the most under-used of them all. The reason for it's unpopularity is not known. Vegeta achieved this form while trying to defeat his constipation in a mini episode, and then later on, his son Trunks achieved the form after a very powerful and much needed kiss from his wife, the beautiful Android 18. Since then, the form has really not made an appearance, but since it is one of the favorite forms of the creators, it is rumored to be making a return in the near future.
Users: Adrian, Goku, Vegeta, and Future Trunks

Legendary Super Saiyan:
This form is a unique and very rare Super Saiyan transformation rather than just a title. The result is a Super Saiyan with a seemingly endless supply of energy. It is a form spoken of in ancient Saiyan folklore.  This transformation puts it's user(s) in a class all of their own. It's power is between that of a Super Saiyan 2 and 3. The main difference between Legendary Super Saiyan in Robot Ball Z, compared to Dragon Ball Z, is that the user of this form gains blue hair, not green-ish yellow like in the movies. The user also gains a tremendous size, similar to the Non-Canon Robot Ball Z exclusive form "Super Saiyan Large".
Users: Broly and Broly Jr.

Super Saiyan 3:
This is the third form the Saiyans are able to obtain. This form is only obtainable through extreme emotional anguish or amazingly difficult training in the chamber. That was true until Gotenks achieved it anyway. Their transformation was less than impressive to say the least. In typical kid fashion, they achieved the form by farting loudly on the battlefield in Season 3.
Users: Goku and Vegeta
Fused Users: Gotenks

Forms created that were made by the creators of robot ball z

Super Saiyan Large:
This is a form forces it's user to grow to an abnormally large size. How powerful it is hasn't been confirmed, but it's rumored that it's power is close to, but not as powerful as a Super Saiyan 3  like the Legendary form. Later on in the series, more  information will be revealed about this enigmatic transformation. Although it seems this may not happen as Future Goten is leaving the show in Early Season 5.
Users: Future Goten, Future Trunks, and Vegeta

Super Saiyan True:
This form is rumored to be the most powerful form that any Saiyan will reach in Robot Ball Z. Unfortunately for us though the creators have revealed that it won't make an appearance until the very end of Season 3 at the earliest . In this form, the Saiyan using it reaches their full potential, making them the most powerful version of themselves that they could possibly be. This form is only achievable by those who go through many stages of hell. This is RBZ's version of Super Saiyan God.
Users: Future Great Saiyaman, Goku, Vegeta, and Vegeta Jr.
Defunct Users: Future Trunks


???
The creators of Robot Ball have revealed that they are going to create one more Super Saiyan form. It's rumored that one it will make it's debut in Late Season 7. This form is supposedly so powerful, that it's user(s) can only hold it for a matter of minutes before passing out, so it is only to be used in dire situations.
Users: It has been stated that this form will only have one user.

transformation add-ons made by the creators of robot ball z

Ascended Legendary Super Saiyan:
This form's power rivals that of a Super Saiyan 4. It is used by Broly Jr. to surpass Super Saiyan 2 Future Trunks who was matching his Legendary Super Saiyan Form. How it is achieved has not been revealed but it's assumed that Broly Jr's magic was involved with it. It seems that the only men that can possibly stand toe to toe with an Ascended Legendary Super Saiyan are those who can become Super Saiyan True, As seen in Season 5 when Vegeta Jr. defeats Broly Jr. with Bardock.
Users: Broly Jr.


Ascended Super Saiyan 3: 
This is the final branch of the advanced Super Saiyan forms in Robot Ball Z, achieved through a need, not a desire. In the form, every nerve is concentrated, sending ki through the body. It raises both power and speed. It is a forced increase in the power output of the initial transformation, and thus is not in an actual transformation. This form was placed into Robot Ball Z to make use for Golden Haired figures. Thus, being "Ascended" makes the Saiyan's hair gold.
Users: Goku