My favorite theory on how did Homura became so powerful is simple and elegant her wish . Laws of Madoka Magica universe are simple and consistent and the most basic of them says that if you state a wish , you get to become a magical girl and your wish will come true . Now let ' s take a look at Homura ' s wish I want to redo my meeting with Kanamesan . But instead of being protected by her , I want to protect her ! . see the last part ? Homura ' s potential to become a demon to Madoka ' s god exists because it needs to exist in order for her wish to come true . At first , Homura thought her journey as Madoka ' s guardian has ended with Madoka becoming a god , but she realized that ' s not the case , when Madoka told her in the movie , when she didn ' t have memories of being a god , that she cannot possibly imagine herself leaving people she loves behind , for whatever purpose , because it would be too sad . Thus making Homura regret letting Madoka state her wish and deciding she ' ll make her human she used to be again . That also explains Homura ' s line before she did what she did I ' ve been waiting for this moment . How could she be waiting for this moment if she couldn ' t possibly know about her boost in power in advance ? She ' s not referring to the act of pulling Madoka out of heavens , she ' s simply referring to the act of protecting Madoka from becoming anything more than ordinary middle school girl , which is something she ' s been waiting for since she made her promise with Madoka in one of the very first timelines . So do I think it was bad decision on Homura ' s side ? No . EDIT someone pointed out that this is partially explained in Wraith arc manga , which I own , but haven ' t actually read yet , so I don ' t know anything about their explanation and how does it or doesn ' t conflict with my theory .