User blog comment:Guildmaster Grovyle/JLE Role Play, Winter 2015-2016/@comment-7345250-20151212224036

(Off-record) I might as well compile the list before I start forgetting. Here are the clues that hinted at the mysterious Mare Do Well's secret identity:
 * Complete refusal to talk whenever Discord, Twilight, or anyone who knew her was around. She realized that they would recognize her voice. She only spoke in Ponyville after her spell deafened the Mane Six.
 * I made numerous remarks about her "imposing stature."
 * Having a horn longer than Goldfin's. Not even Lady Justice could boast that.
 * Reaching HQ without obviously teleporting.
 * Uncommonly powerful magic often based on light.
 * Thanking Acolyte for doing her a great favor, i.e. reuniting her with Luna after the battle for Canterlot. It meant a lot to her.
 * Unnatural levels of serenity and wisdom. She talked Acolyte into destroying his own creations, only raising her voice with him once.
 * Parlys caught sight of something that fascinated him when he knocked her over. That thing was a pair of wings.
 * Recognizing Phantomenia. Well, actually, she thought it was Philomena at first glance. Those emotion checks were very detailed.
 * Reminding Phantomenia to stay hidden. She knew that the sight of her alongside a phoenix would immediately reveal her identity to anyone looking.
 * Referring to Phantomenia as a "smart girl" or such on several occasions. I nearly had her say "young lady" once.
 * Quoting Star Swirl the Bearded to Strongheart.
 * She knew the exact location of Fluttershy's cottage and enough about the owner's personality to assume she wouldn't miss a bag of bird feed given to a phoenix.
 * She knew a little about the Mare Do Well myth and the costume at Ponyville Town Hall.
 * She saw something in the schoolhouse that troubled her. It was a framed photograph of herself.
 * She was awake before the sun rose.
 * Apprehension about returning to Canterlot.
 * The hypothetical question about flying into the forest was an indirect way of checking if Phantomenia had caught onto the fact that she, too, could fly.
 * Peaking at the desert trolley. The princesses share a sweet tooth, remember?
 * Doing it all for the future of Equestria.
 * In the chat room I insinuated a few vague things about the Mare Do Well's magic aura and general patriotism to throw suspicion upon Nurse Brokenheart and Lady Justice. Those were supposed to be misleading. (Gotcha, UP.)
 * I also mentioned in chat that I was thankful that Spike wasn't around. Why? If he had sneezed on a letter or something, it would have appeared right above the Mare Do Well's head.
 * The Mare Do Well's vector has been on my DeviantArt since last month.