Rumours and secrets that bode ill for Equestria's future trickle from the Griffon kingdom. Celestia and Luna are uncertain Ironclaw will continue to honour the peace treaty between their two great nations, and after 700 hundred peaceful years, the two Princess will not allow such a travesty to ever terrorise their kingdom again.
Twilight Sparkle and Trixie Lulamoon are halfway through training Moondancer, Starlight Glimmer and Sunburst in the Assassin's art when they are summoned for a journey that will take them into the Griffon Kingdom's heart; Ironclaw's impenetrable throne room.