Dragon Ball Z has many iconic transformations, but few are as awe-inspiring or ridiculous as Super Saiyan 3. This form is unique in many regards, as it's first introduced off-screen and maintained as a secret form Goku accesses while in Otherworld. For many reasons, it feels like the most alien of the Super Saiyan forms. No eyebrows? Extra-long hair? Incredible power? Super Saiyan 3 is a strange transformation.
However, there are many secrets surrounding the Super Saiyan 3 form. These details are less obvious, maybe even hidden, but help make it an even odder transformation that might be more trouble than it's worth by the time of Dragon Ball Super and Dragon Ball GT.
Super Saiyan 3 Was Originally Going to Feature Regrown Tails
The Super Saiyan 3 form did not emerge fully completed. Early sketches by Akira Toriyama indicate that, at one point, the transformation wasn't just going to feature Goku and Gotenks growing a ton of hair and losing their eyebrows. Rather, Saiyans would also regenerate their lost tails. Interestingly, this concept would later be recycled in the Super Saiyan 4 form, where Saiyans actually did regrow their tails.
Of course, this was far from the only scrapped idea surrounding Super Saiyan 3. At one point, a Super Saiyan 3's hair was not nearly as long as it ultimately became. Instead, it more closely resembled Super Saiyan 2. As these sketches were rejected by Toriyama in the end, they show the creative process for the Super Saiyan 3: either too similar to the previous forms or far more alien.
Super Saiyan 3 Doesn't Require Intense Emotion to Transform
While Super Saiyan 1 and 2 require intense emotional triggers, it is not certain that Super Saiyan 3 requires that same level of inner intensity to transform. Goku's first transformation into Super Saiyan 3 happens off-screen but is apparently a product of intense training. Gotenks transforms into Super Saiyan 3 effortlessly -- though, considering Goten and Trunks's similarly easy Super Saiyan transformations, this isn't surprising.
Even in the various non-canon transformations, going Super Saiyan 3 doesn't seem to require raging inner emotions, but is rather a result of pushing oneself further beyond their previous limits. It is also one of the few Super Saiyan transformations that doesn't suggest an emotional alteration. This implies that Super Saiyan 3 isn't tied to emotional stability, but relies more on sheer determination.
While many instances of untrained Super Saiyans showcase the characters in question drawing from intense emotions, the same is not true for Super Saiyan 3. On top of that, the form doesn't seem to affect the users' personalities or behavior like earlier transformations. Unlike Gohan's aggression as a Super Saiyan 2 or Goku's rage as a Super Saiyan, Super Saiyan 3 Goku and Gotenks just act like themselves.
Super Saiyan 3 Has Only Two Canon Transformations (But MANY Non-Canon Ones)
To date in Dragon Ball Z canon, there are only two canon Super Saiyan 3s: Goku and Gotenks. There are, however, several Super Saiyan 3s who exist in non-canon works, such as Super Dragon Ball Heroes, Dragon Ball Xenoverse and Dragon Ball: Raging Blast. The first example was Broly in Raging Blast, followed by characters like Vegeta, Bardock, Raditz, Nappa and Trunks. Many of these fan transformations are not given explanations for how they transformed.
The proliferation of Super Saiyan 3 outside of canon has resulted in some fans forgetting just how rare this form truly is in the real story. Vegeta accessed both Super Saiyan 4 and Super Saiyan Blue without ever reaching Super Saiyan 3. In the current canon, the only character who seems poised to transform into a Super Saiyan 3 is Caulifla, due to Goku half-suspecting that she'd transform during his fight with her.
Super Saiyan 3 Might Genuinely Kill The User
The Super Saiyan 3 form consumes a great amount of power. Kid Goku in Dragon Ball GT can barely maintain it for more than a few minutes. Transforming into a Super Saiyan 3 also decays the Gotenks fusion at an accelerated rate. However, there is reason to believe that this transformation can actually kill its user -- though the source for this theory is speculation in a non-canon work.
In Dragon Ball Z: Xenoverse 2, Bardock transforms into a Super Saiyan 3 while fighting Mira. When the fight ends, Bardock is nowhere to be seen. Trunks speculates that the transformation might've consumed so much power that it became unstable, obliterating Bardock's physical body -- or that the amount of energy generated punched a hole in reality through which Bardock slipped.
This isn't as unfounded as one might think. There are various techniques that kill or hurt the person using them, such as the Evil Containment Wave and Kaio-Ken. Super Saiyan 3 also has the distinction of dramatically shortening Goku's time on Earth during the Buu Saga. In effect, yes, this transformation can kill the user.
Super Saiyan 3 May Only Be Reachable Under "Unreal" Circumstances
No one in canon has naturally transformed into a Super Saiyan 3. Both Goku and Gotenks transformed under particularly odd conditions. Gotenks is a fusion, but neither Goten nor Trunks can transform on their own in canon. Gotenks first transformed in the Hyperbolic Time Chamber, where Gohan years prior briefly transformed into a Super Saiyan 2 but couldn't maintain it.
The only non-fusion to achieve the form in Dragon Ball canon is Goku. He first discovered Super Saiyan 3 while dead, and demonstrably had difficulty using the form once restored to life. Many of the non-canon Super Saiyan 3 forms only transpire after time travel and demonic energy affects said characters, indicating that those transformations are not natural either.
All of this indicates that the Super Saiyan 3 transformation might be impossible to achieve under normal circumstances. It may require fused Saiyans or being divorced from the normal laws of reality in order to truly uncover this unique form. This is certainly evidence indicating that the Super Saiyan 3 form is not bound to the same laws other transformations follow.