

However, in the case of the Legendary Super Saiyan, Broly's hair and aura both turn into a shade of green. This change, though subtle, signifies the difference in power between the Legendary Super Saiyan and the regular Super Saiyan.
4. The term Legendary derives from the Saiyan's inherently bloodthirsty nature
Before the emergence of a Saiyan like Goku, who is inherently friendly and peaceful, Saiyans were always regarded as a warlike race, ruthless and wreaking havoc across galaxies. While many argue that this is merely a result of being ruled by Frieza, it cannot be denied the atrocities this race has committed in their universe-conquering endeavors.

The term Legendary Super Saiyan is perhaps a reverential term used by ancient Saiyans to denote individuals always craving battle and destruction, spreading chaos wherever they tread. Therefore, any individual capable of reaching this level of power would be akin to a monster, a fact readily understandable.
3. Only once every 1000 years does a Legendary Super Saiyan appear
There is a piece of lore mentioned by Vegeta regarding the appearance cycle of the Legendary Super Saiyan. Legend has it that such an individual appears once every 1000 years. This indicates that this transformation is incredibly powerful and rare, although it seems the lore has caused some misunderstanding among the audience.

Vegeta further adds that he is the last Super Saiyan to appear in the past 1000 years, which seems contradictory to the previous lore. However, in Vegeta's context, he does not mention the appearance cycle of Super Saiyans. Therefore, his assertion probably refers to the appearance from 1000 years ago of the Legendary Super Saiyan - the predecessor of Broly.
2. Legendary Super Saiyan could be the true form of a Super Saiyan
Another interesting piece of information that Vegeta revealed to the audience is that the Legendary Super Saiyan could be the actual transformation of a Super Saiyan, as described in ancient legends. If this is true, it means the transformation process of both Goku and Vegeta as well as their offspring may have had some errors or defects. It also explains why there are so many different levels of Super Saiyan transformations.

Meanwhile, the Legendary Super Saiyan form appears to have reached the ultimate state. It does not have any additional levels; both Kale and Broly transform directly to this level from the start. However, if this setup were to change in the future, Dragon Ball audiences wouldn't be too surprised.
1. Form taps into unlimited power
The Legendary Super Saiyan plunges the user into a frenzy... unless they can master the power. It seems to stem from the user coming into contact with an immense and boundless energy flow.

Thus, with the Legendary Super Saiyan, users will never run out of power or reach their endurance limits. They become extremely formidable opponents. If not convinced by reason, the battle with the Legendary Super Saiyan is likely something no one desires.