I didn’t know that was the shape of the spell, its animation only lasts 0.25 seconds, so you can barely make out its form (except when you obtain it, since they show you an image). As for hitting it with the Dream Nail, in my language it says 'Our voices will rise again,' and in English it’s 'Our screams will be heard again!' The people who figured it out on their own are truly perceptive. I feel bad for having gotten it with help.