She visits several planets she believed were part of the new Kryptonian Empire ruled by Brainiac (whom she sees as her father) only to find them devoid of life. Several times before it's also shown that Brainiac can trigger a sort of mind control over her, which she can never remember. Later on, desperate to find out what happened, she finds a mural on Thanagar that depicts a Kryptonian exterminating Thanagarians, which triggers a surge of scattered memories and causes her to scream that she can't remember any of it. After that she confronts Brainiac about all this, he claims that all those worlds were "unworthy of the Kryptonian Empire" and he used Kara to wipe all of them clean, but because she was a softie and never fully obedient, he had to use mind control which is why she can barely remember any of it. This entire revelation causes Kara to wholly turn against him and join "the good guys".