Both. But it's not entirely up to her. There are other forces at work. The Fal'cie and the l'Cie are her creations, but she never intended for them to become monstrous or warped.

The l'Cie were meant to be her soldiers - her messengers - for a better world.

{Opening the door, she ushers Serah inside.}

Each was given a Focus that would act as a catalyst for change.