Unlocks at 7 stars.
Below are the requirements to enter the event. Once you meet these requirements, you will be able to start earning tickets that are needed to attempt the event itself.
The last set of requirements have been released. [Link]
The second set of requirements have been announced
Galactic Legend events are permanent events that will become available once you've met the requirements. The requirements are gated by relic and gear levels. [link]
The first requirements needed for the new Galactic Legend events has been added to the game. [link]
There is no history for this event.