Despite his best attempts at trying to save the remnants of Krypton's civilization, Kara Zor-El's (aka Supergirl) father Zor-El inadvertently doomed his people. The tragic origin of Supergirl was revealed to be even worse than she thought when she finally recovered her memories of her last days in Argo City.
The destruction of Krypton is strongly associated with Superman, as it's the reason his parents sent him to Earth. But baby Kal-El was far from the only person affected by the nightmare of their home world's final days. Kara Zor-El was a teenager when the dreaded data-harvesting villain known as Brainiac brought his evil to Krypton and his attack left Kara shaking for years after. Unlike Superman, who was rocketed to Earth, Kara and a handful of survivors lived on after Krypton exploded in a protected community known as Argo City. For a brief time, the Kryptonian race had the chance at normalcy in spite of the great tragedy they'd suffered.
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Unfortunately, the very thing that was aimed at protecting them was ultimately their undoing. In Supergirl #35 by Sterling Gates and Jamal Igle, Kara is continuing her reunion with her parents now that Superman has liberated the Bottle City of Kandor. Things take a turn when Zor-El realizes his daughter has been suffering from kryptonite poisoning. Zor-El and his wife Alura put their daughter through a process to heal Kara, and inform her that she may recover memories she had forgotten. As the process commences, Supergirl does remember marveling at the protective shield her father helped create to protect Argo. She also recalls discovering that the shield was powered from a defunct Brainiac probe and
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