It has been three months since the catastrophic attack on Canterlot by Sombra's army. Twilight has yet to truly recover from the event that she blames herself for. But the forces of Darkness are striking again in search of the Etna Key to free the dreaded Red-Black Beast. With time now short, Twilight and her friends must find the Etna Key before it's too late.
Spike never went down the stairway to save Twilight from Sombra's door. This is what happened after.
Twilight has done things she regrets. Things that she wishes she could take back. But nothing she can do will ever fix the past. And when the forces of Darkness at work again, she fears she may only have more regrets.