This story is a sequel to The Dresden Fillies: False Masks

It's been a while since the girls have seen their good friend Harry Dresden. Discord escaped, Luna attended her first Nightmare Night, the Royal Wedding was crashed by hordes of changelings, and Pinkie Pie threw a statistically improbable number of parties. They tried inviting Dresden, but between his new job and new apprentice, he always claimed to be too busy. The solution was obvious; if he couldn't come to his friends, they needed to go visit him. Besides, they say Earth is lovely this time of year. What could go wrong?

This is the story of Gemini Constel. A unicorn: warlock class, fresh from the grave, asked to help fight the darkness that has manifested inside Equestria and beyond.

Maybe.