Someone managed to travel through space and time and managed to gather a copy of the essences of villians throughout history. Created out of the melded essences of Sombra and Chrysalis, this is how Euthemia was came to be.  
Despite being born of such dark essence, she is not innately bad of heart. Rather, she is confused about her identity. She doesn’t know who she wants to be, nor who she is expected to be, as her creator left her behind after her creation. What will come of her is hard to tell. While she is of changeling nature, whether or not she is redeemable is questionable.
 
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