Karla-Gard's universe

In a parallel universe, River Song remembered being hunted by the Karla-Guard "all her lives".

In this universe, she was successful in killing the Doctor, as well as her captors, during an event which became known as the Massacre of Demon's Run. Using her TARDIS, she was able to cross over to N-Space via a rip in dimensions, where she met another version of herself.(AUDIO: The Two Rivers)