<Tr> <Th> 18 </Th> <Td> 18 </Td> <Td> "Worlds Finest" </Td> <Td> Nick Gomez </Td> <Td> Story by: Greg Berlanti Teleplay by: Andrew Kreisberg & Michael Grassi </Td> <Td> March 28, 2016 (2016 - 03 - 28) </Td> <Td> 4X7618 </Td> <Td> 7.17 </Td> </Tr> <Tr> <Td_colspan="8"> <P> Siobhan discovers that the women in her family are cursed with the spirit of a banshee, which can only be quieted by killing whoever wronged them . Deciding to kill Kara, Siobhan frees Livewire from captivity at the DEO and suggests they team up to kill both Kara and Cat . Siobhan--now calling herself Silver Banshee--and Livewire kidnap Cat and wreak havoc on National City Park . Meanwhile, Supergirl has a run - in with Barry Allen / Flash, a superhero from an alternate universe, whom she asks for his help to find Livewire and Silver Banshee . After a climatic fight in a downtown park, Kara is able to subdue them and win back National City's trust . At the end, Kara decides to reveal her romantic feelings for James only to discover that everyone in National City has fallen under some kind of spell, revealed by Non to be the result of Myriad . </P> This episode is a crossover with The Flash . </Td> </Tr> <P> Siobhan discovers that the women in her family are cursed with the spirit of a banshee, which can only be quieted by killing whoever wronged them . Deciding to kill Kara, Siobhan frees Livewire from captivity at the DEO and suggests they team up to kill both Kara and Cat . Siobhan--now calling herself Silver Banshee--and Livewire kidnap Cat and wreak havoc on National City Park . Meanwhile, Supergirl has a run - in with Barry Allen / Flash, a superhero from an alternate universe, whom she asks for his help to find Livewire and Silver Banshee . After a climatic fight in a downtown park, Kara is able to subdue them and win back National City's trust . At the end, Kara decides to reveal her romantic feelings for James only to discover that everyone in National City has fallen under some kind of spell, revealed by Non to be the result of Myriad . </P> <Tr> <Th> 19 </Th> <Td> 19 </Td> <Td> "Myriad" </Td> <Td> Adam Kane </Td> <Td> Yahlin Chang & Caitlin Parrish </Td> <Td> April 11, 2016 (2016 - 04 - 11) </Td> <Td> 4X7619 </Td> <Td> 6.12 </Td> </Tr>

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