Oozaru: This is the "giant monkey" form, originaly, the saiya-jins can control that form, but Goku and Gohan can't really control it (they were never taught to), only Saiya-Jins with a tail can reach that form, and they need to look at a full moon (original or artificial) to become Oozaru. The Saiya-Jins used that form to conquer other planets, because they are 10 times stronger in Oozaru form.
Super Saiya-Jin (SSJ): Original SSJ form, with yellow hair standing up, and yellow eyebrows, and green eyes, in this form the saiyan is much stronger and faster. Only a Saiya-Jin with a pure heart can turn SSJ pure good, or pure evil!! and it must be awakened by rage and fury, to turn SSJ the first time. SSJ Dai Ni Dankai: (USJ) Like the original SSJ form, much stronger, but a little bit slower. More muscular mass.
SSJ Dai San Dankai: (USJ2) Like USJ, More spiky hair, much stronger, but much slower too... SSJ2: Like SSJ, but totally différent hair style, very spiky hair, lightnings around the body, much stronger, much faster. SSJ3: Like SSJ, but with very long hair, falling down to the waist, no more eyebrows, lightnings, much stronger and much faster.
Ougon Oozaru: Like the Oozaru original form, but with yellow hair and fur, you also need a tail, and a "full earth" to turn Ougon Oozaru (from another planet) stronger than SSJ3. Kind of SSJ Oozaru, it's said to be the original SSJ form.
Transformation 4: If a Saiya-Jin is able to control the Ougon Oozaru form, and that he's able to concentrate the energy, he can transform into that form. He's got black hair, and red or dark pink fur on his torso, and his eyelids are red, and he's got a new eyes color: yellow, or blue.
