Goku Black in his Super Saiyan Rosé form with a closed fist and his eyes closed


This Rare Dragon Ball Form Was Only Reached by One Person
The rarest Super Saiyan form in “Dragon Ball” is one of the few only ever achieved, and likely only ever attainable, by just one character: Zamasu.
The third saga of “Dragon Ball Z” sequel series “Dragon Ball Super” introduces the villain Zamasu who, in a parallel universe, takes Goku’s form and becomes known as Goku Black.
His sole Super Saiyan transformation looks similar to the Super Saiyan form, but his hair turns a shade of light pink instead of gold, which is why it’s known as Super Saiyan Rosé.
Thus far, even in the “Dragon Ball Super” manga, which has surpassed the anime by a couple of story arcs, Goku Black is the only character capable of going Super Saiyan Rosé.
The reason Zamasu ends up with a unique appearance rather than the typical Super Saiyan or Super Saiyan Blue form is because he was once training to become a Supreme Kai, a god.
By taking on the countenance of a Saiyan as Goku Black, he can go Super Saiyan, but his divine energy makes the ability manifests differently than it does for a regular Saiyan.
Since no other gods in “Dragon Ball” have or seem likely to ever want to become Saiyans, Goku Black should remain the only character to ever go Super Saiyan Rosé.