King Sombra : “You have not succumbed to the fear of my shadows but know that, in this world, there is things way worse than me. Don’t you remember the horror you felt as a child ? At that time you only faced the master, but you didn’t see the city, you didn’t see its tall windowless towers that reach up to the starless sky and filled with unspeakable things where I lived, you didn’t move along its narrow streets not made for creatures of your world and eternally bathed in shadows. 
Don’t you hear them Celestia? Don’t you hear the bells? The bells that shouldn’t be, sending their music from beyond the great sea of stars, from beyond space and time themselves, sending a warning to all the worlds : the horrors of the past are still here, not alive but not dead either, defeated but not destroyed… “