Because it takes the concept of superheroes into a whole new level and we finally have an episode where Spike is the main character for once. I was also surprised to see Fluttershy get mad which rarely happens in the show and Andrea Libman nailed it. Ironically, the way Andrea did the scene where Fluttershy got mad without trying to sound like Pinkie Pie is actually impressive. It’s a shame we never got a sequel but either way I enjoyed it