The legendary trait is a very rare, There is a 5% chance of getting the trait, anyone can obtain the trait upon character creation, once the eye of cthulhu is killed if the player has the trait the player will gain a buff called ??? . After obtaining Legendary Super Saiyan the buff name changes to Legendary and saying "You are the saiyan from the legend" . The bar can change of color depending of the trait, in this case the Legendary Trait .
The passive effect of the legendary trait is x2 maximum ki, also granting access to Legendary Super Saiyan and Legendary Super Saiyan 2, which restricts Super Saiyan 2 and Super Saiyan 3. Super saiyan god can also not be used on command while having the legendary trait, though it can be used once you have picked up the item required for it until you run out of ki.