In the fight with Caine, the ninja draws his knife twice.
In the fight with the ninja, Caine grabs his sword by the blade to throw it away, revealing it is a fake.
In 'The Assassin', Master Po quotes "awake at dawn with a winged heart and give thanks for another day of loving". A very specific phrase from Kahlil Gibran's 'The Prophet' which would not be written for roughly a century.