The title comes from William Shakespeare's Henry V, Act 1, Prologue, which starts, "O for a Muse of fire, ..."
The original Huntress was the daughter of Bruce Wayne and Selina Kyle (Batman and Catwoman)
This is the first Arrow episode without flashbacks.
Helena Bertinelli's fiance's name is shown on his gravestone as Michael Staton. The artist who designed the Huntress super hero in the comics was Joe Staton.