Transcript:
Phoebe: The net thing we need is a MYSTERY to solve! Know of any? Marigold: We could investigate inexplicable magic that is sunlight on dewy morning buttercups in a sylvan glen! Phoebe: That's not very gritty.Marigold: You did ask a unicorn.
There are grimdark MLP fanfics, but I doubt the cartoonist likes them.