In the aftermath of the Memory Stone's destruction, Wallflower reveals to Sunset that she erased more than just the Rainboom's memories of Sunset. She erased Sunset's memories of Wallflower, too.
Seeing as Lightning Dust is now a reckless, self-centered pony who throws caution to the wind, Rarity wants to ask her what happened -- where the time went and why she changed. But she won't. Because Rarity knows what happened. Life happened.
A call for help from an old friend takes Rainbow Dash to a place she'd rather have out of her life... but her business there isn't finished. She'll have to discover how to resolve and close a painful chapter of her past for good.
After three years, Rainbow Dash comes home to Ponyville. The war's won and she's back, having served Equestria with honor. But after what it's taken out of her - and left lingering - is it so simple? Can she come home again so easily?