Starburst is a aquatic clone of Kara from a time in the future where the world has been flooded but the starburst group, a group of aquatic creature who where tiered of land dwellers doing all the bad stuff so they flodded it and made closes of KAra since her dna was... (I dunno I never thought it through very well)

Long story short, she's no longer working for the group and can breather in water or breathe air.

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