There isn't much behind this picture. I considered this: if Twilight was such a talented magician now, I can only imagine how much of a difference years into old age would take her. The extent of her powers would be under full control. I tried to add a few things that showed age, such as a few grey streaks in her hair and crows feet, but most of it got eaten by the glowy goodness.
I've had ideas for a comic using an aged Twilight Sparkle, but it's sort of depressing. Maybe I'll start it out and see where it goes.
EDIT: I'm sorry! There was a slight error in the first picture. If you re-blogged this and you're reading this, THIS is the fixed version!!