Super Saiyan-Jin Level 4icpg1252\uc1 \
SSJ 4 is the last and final stage of a Super Saiyan-Jin. I am still a little confused about this final stage, but I hope to provide the most accurate information as possible. This stage is called "Beyond Super Saiyan-Jin". To become a SSJ 4, the Saiyan-Jin must have a tail and plenty of strength (so the Saiyan-Jin can expand it's current strength and power to get to SSJ 4). Like the very beginning, when the Saiyan-Jin looks at a full moon, he/she is instantly turned into a Gold Oozaru, or a big golden monkey (see picture to the left). While the Saiyan-Jin is in Oozaru mode, he goes berserk to expand his anger and strength, hence becoming SSJ 4. SSJ 4 is not a big monkey, SSJ 4 is actually transformed back to a human-like Saiyan-Jin. With long black hair, green eyes, red fur covering most of the body except for the chest, and a long red tail. They still have that yellow glow around them. This represents that the Saiyan-Jin is in SSJ mode, however, it is weak glow not like SSJ, SSJ 2 or SSJ 3.  Personally, I do not believe this stage is the most complete. It might gain the most strength/speed/agility, but the transformation is far too awkward. First the Saiyan-Jin needs a tail and a full moon to get to Gold Oozaru mode. Then after that the huge monkey needs to expand his/her own power to get to SSJ 4. I don't know if I am correct or not, but this process is too slow.
Advantage:
 It increases the overall strength/speed/agility. Which ultimately makes SSJ 4 greater fighters than SSJ 3.
The strength, speed and agility are well balanced out, no need to readjust them to suit the Saiyan-Jin like SSJ 2.
Disadvantage:
It uses up too much power, just like SSJ 3. This transformation does not last long. After 10 minutes or so, the Saiyan-Jin transforms back to a normal Saiyan-Jin.
The transformation takes too long, unlike the transformation from a Saiyan-Jin to any of the other Super Saiyan-Jins (1, 2 or 3).
Interesting Facts:
Once again, Gokou has proven himself to be the greatest Saiyan-Jin, by achieving to this level without any artificial help. Gokou reached this level purely based on his own determination and his hard work.         
 Vegeta cheated to reach this level by the use of a Brute Ray created by Bulma. This ray enabled him to grow his tail back so he could go on rampage as a Gold Oozaru and become a SSJ 4.
 From the above two points, we can see that Gokou was the first to achieve this transformation, Vegeta second.
 Gogeta is the first combined Saiyan-Jin to become a SSJ 4.        
 Since the GT series isn't created by Akira Toriyama, but his crew at the Bird Studio. The transformation to SSJ 4 is nothing like the previous transformations (don't we just love the gold hair?).
Who Can Reach This Form:
Goku, Vegita (artificially), Gogeta, and Brolly (if he were alive)                                     (If only Gohan was able)
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