Chrysalis WON. But not for long.

Twilight is upset at the loss of her brother, Cadence is upset at the lost of her love, and Sombra is more then willing to 'help' them use that hate.

So in my mind this is if Cadence and Twilight never escaped the crystal caverns but somehow Sombra found out about them and used his unicorn powers to bring them to him. I dunno if he’s in love with either of them, maybe Twili but Cadence is being rather cold, her would be hubby did probably get gobbled up after all, but for whatever reason he decided to help them take Canterlot back, thus saving most if not all the rest of Equestria. In my headcannon, Sombra went insane after watching the crystal queens strive to make her people happy to no avail and dying via sacrifice to the crystal heart (in my head the Crystal Heart used to work like that evil rock thing in Disney’s Atlantis until the crystal fair was invented) so maybe he sees his former friends/love interests in Cadence, only sexier because she wants (epic Goliath voice) REVENGE. Twilight doesn’t trust him, but in my mind it’d kinda be cuter if, after seeing Cadence’s hatred and realizing maybe ruling with love and happiness is the better way, and changes his ways and gives Canterlot to Luna to run and he and Twilight go rule the Crystal Empire. Maybe I should write a fanfic…