 Due to unforeseen scheduling problems with Shaft , production for the series was postponed for three years following the completion of its writing . However , once the issues were resolved , production began without any further complications . The animation studio spearheaded the conception and design of the witches in the series , as well as creating each one 's individual backstory . Urobuchi had originally envisioned the witches to be similar to conventional monsters such as Godzilla , but upon seeing the surreal concept art for one of the main witches , Walpurgis Night , he remarked : " How can Homura possibly fight against something like this ? " Designers from Shaft also added quotes from the German folklore legend Faust to the series . Throughout production , the animation production team <unk> Inu Curry had freedom to insert new details or modify existing ones from the original script . An example is during a scene in the final episode where the team added black wings to Homura , something which was not included in Urobuchi 's writing . Urobuchi praised this aspect of the production , commenting that " additions by the animation production team added more mystery and depth to [ the ] characters , and without them , it would have been very difficult to write any further stories in the world of the series " . 
