In their haste to rescue her from the Phantom Zone, Supergirl‘s friends forgot to take the Arrowverse’s Crisis on Infinite Earths into account. Where Supergirl was trapped during the season 6 premiere of Supergirl is not the same space prison they were familiar with. A place created to hold the worst of Kryptonian and alien criminals, the Phantom Zone existed outside the universe’s normal dimensions. However, when Crisis radically changed the multiverse forever, it left no stone unturned. All the threats and dangers inside the Phantom Zone have been multiplied as, instead of consolidating the Zone into one Earth or place, Crisis did the opposite, putting the Girl of Steel at far greater risk.
Perhaps the most impactful outcome of Arrowverse’s Crisis on Infinite Earths was the creation of a new universe that combined elements of different multiverse worlds into one Earth-Prime universe. That one universe now contains elements, individuals, and dangers that previously existed in separate dimensions or universes entirely. However, it never occurred to Supergirl and her friends that the events of Crisis would have such a dramatic effect on the Phantom Zone.
When J’onn Jones and the others temporarily open a portal to the Zone, Brainy realizes their error. The existing knowledge they possessed about the Zone is basically null and void. No longer is this Phantom Zone the one-dimensional intergalactic prison they were expecting. Instead, Crisis has mashed together all the Phantom Zones that previously existed, creating a mini multiverse within one extradimensional space. Their plan for Dreamer to quickly locate Supergirl is now almost impossible to execute, which means Supergirl will be at the mercy of the Phantoms’ torture for a far longer time.
Both in film and television Supergirl and her family have strong ties to the Phantom Zone. In fact, Supergirl has been sent or trapped in the Phantom Zone four times. The first time was in the 1984 movie that bears her name where she teamed with a former teacher to escape. The second was during Smallville, which also marked the television introduction of the Phantom Wraiths who existed to torment Zone prisoners. When Smallville’s Supergirl escaped, one of the Wraiths was let loose into the world too. In the Arrowverse iteration, Supergirl has now visited the Phantom Zone twice, and in their attempt to free her, Supergirl’s friends have repeated history and allowed a Phantom to escape and terrorize Earth. Also, in that version, Kara’s father Zor-El created the Phantom Zone, and her mother Alura, as a judge, sentenced dangerous prisoners to be banished to the Zone or its adjacent maximum security facility Fort Rozz.
Supergirl herself is equally, literally and figuratively, in the dark about the serious dangers of this new Phantom Zone. Since this Zone was created by Crisis, how can she know for sure which version of Zor-El rescued her? Is this the father she left behind on Krypton? Supergirl is also unable to distinguish how much time is passing in the outside world while she’s in the Phantom Zone, as she has already been trapped inside at least one Phantom-created nightmare. The longer she remains in the Phantom Zone the greater risk Kara loses both her sanity and her life.
Crisis’s impact on the Phantom Zone shown in the season premiere of Supergirl transforms an already formidable terror into an absolute hellscape for Supergirl. She’s the paragon of hope, but hope is the one thing Zor-El tells her she will have to abandon to avoid the Zone’s worst horrors. The Phantoms will inflict more severe punishments, bring to life more fears, the longer she resists. While Kara is likely to cling to hope more fiercely than ever before, this isn’t the Phantom Zone she knew, and she may have to become someone else to survive.
