"The raven flies free under the blood colored moon." or "Having been liberated from impending execution, a raven soars under a full moon that, seen through the shroud of a smokey sky, vaguely resembles the color of blood." or something more succinct that make grammatical sense.
I say "blood colored" instead of "red" because the moon itself actually appears more orange and the school colors are black and orange in honor of the event that inspired the motto. Thanks in advance. :)