An Old Friend (pjo x arrowverse crossover)

I wrote the story for my pure enjoyment. It won't be amazing.

Barry, Oliver, Kara and the legends are facing a new threat that is nothing like what they have faced before. Kara thinks she knows someone that can help them with this. This person just so happens to be Percy Jackson (persephone) Who has been her best friend since childhood.

Will Percy be able to help them overcome this threat? And how will the team react to seeing this whole new side of Kara?