Board Thread:Roleplaying/Fun and Games Board/@comment-27363887-20161012212844/@comment-26186871-20170915154708

(This was never mentioned in legend, likely because since everyone in the village was under control... Nobody was "exposing" this-That act of goodness is against the nature of their false destiny.

Fate has swapped before, but while their memories and what they felt their destiny had swapped ("What my Cutie Mark is Telling Me", within the S3 finale "Magical Mystery Cure"), their actual talents did not-That's exclusive to the evil marks. Same thing for personality-Pinkie Pie seemed to not care for farming at all with AJ's mark, and Rarity's sense of fashion came into play as the weatherpony as well-She was trying to make the sky look fabulous.

The cutie mark itself is simply that of cutie marks, not the mind itself-Therefore, their altered mind is, at least partially, a byproduct of the fact that they now have an altered fate-An altered cutie mark. This is apparent with Firestorm's cutie mark of pain and suffering matching the pain and suffering she brought to everypony by starting The Fall. So, what's being changed here? Well, the two spells (MMC vs Starlight/Cutie) are quite different. Let's take a look at the Unfinished spell, shall we?

"From one to another, another to one. A mark of one's destiny singled out alone, fulfilled."

It was only the mark of their fate that had changed-But their real talents and real fate had not been changed. Cutie marks signify fate. But, what if you changed a pony's fate itself? Or gave one to someone who doesn't have any? (Like a timberwolf) Well, considering how when a mark is received, or sometimes just before, one's personality/mind are quite similar to their destiny itself, to sort of go with the destiny, then changing one will change the other. And so.. That's the SCIENCE of Cutie's spell. Maybe. I could have missed a crucial piece of evidence.)