Hey guys so today i am gonna answer a question that some of you might have been wondering but this is not any kind of question this mlp question mlp otherwise known as my little pony a famous tv show and obviously my favorite! So the today question is about Luna .princess Luna was turned into nightmare moon and tried to take over equestria but her her older sister stoped her with the elements of harmony and Luna/nightmare moon was trapped in the moon for a thousand years but this is not it the question is what is wrong with Luna’s flank? She has spos on her flank, now I noticed something in the episode “A royal problem “ in starlight glimmers dream both Luna and tia which stands for celestia were both villains,nightmare moon and daybreaker,so what I noticed is tia’s flank she had spots too but firey so in conclusion the spots on the luna’s flank are a part of her villain self, ask more questions about mlp and I will give you clear answer,bye bye.!