This isn’t really organized, these are just some ideas I was coming up with while brainstorming. See my previous post too, if you haven’t yet [x]
Triggers: Aurora’s Eclipse form is a worst-case scenario. It isn’t a method that she would resort to just for the sake of it. She has to either be forced in to it or manipulated in some way. If Aurora is fed too much negative energy, especially if she is in a meditative state, that negative energy will influence her and her darker side can take over. I imagine this could also happen if she’s made angry enough, like witnessing the people she cares about being defeated and she’s unable to help. It could also probably happen if Aurora isn’t strong enough to save someone or stop an enemy, and I hate to make the comparison but it becomes one of those Emperor Palpatine “Give in to your hate~” situations where she thinks maybe she can protect everyone if she pushes herself even further and uses the dark energies that she has always avoided tapping in to.
Personality: As I’ve stated in my previous post, Aurora is not herself when she is in her Eclipse form. This doesn’t mean that she’s possessed (like Amy in HHNF) but that she is just the essence of everything Aurora is against. This form is not capable of empathy or hope. She is destructive, violent, and relentless. And when Eclipse!Aurora realizes what she’s turned in to, that’s sort of the final straw. Aurora is supposed to be the symbol of hope and light, and the fact that even she can turn in to something evil makes her believe that there really is no such thing as ultimate good.
Weakness: The Eclipse form is strong, but slower in speed. This form is also incredibly draining, so staying in this form will lead to death, whether it’s purposeful suicide or just from staying in the form for too long.
Motive: Eclipse’s motive is not to become all-powerful or to rule the universe. Instead, she wants to wipe out everything. At this point she has lost sight of all the good in people and deems the planet not worthy of saving. She can only see the darkness in everybody and believes that destruction will allow for a complete reboot and the world can start fresh. In order to do this, Eclipse absorbs all light and energy from others and uses her body as a vessel to store this power. When she’s collected enough, she will explode in to a sort of super nova, wiping out everything and everyone, herself included.
Appearance: She loses almost all saturation to both her clothes and her fur. Her usual tan fur becomes a gray-blue, and her pink fur becomes Vantablack in color (If you are deathly afraid of darkness/emptiness I don’t advise looking this up. If you’re not then do it because it’s amazing!) with a sort of marble texture. Her quills are mostly pointed downwards. Her eyes become a ghostly whiteish blue, with her pupils fogged up. As soon as she transforms her inhibitors are instantly drained and break. She tears off her normal jacket and shorts since these were laced with inhibitors that are pointless now.
Other than that, I’m sort of leaving the rest up to interpretation unless you have further questions :)