Never look a gift horse in the mouth, wrote St Jerome (342-420) on the epistle to the Ephesians, but be careful at a suspicious sacrifice of a knight !
In the Bible, Revelation 6 : 8 , " ... and I looked, and behold, a pale horse, and his name that sat on him was Death ... " , so be double careful when it is a white knight !
By the way, A horse ! a horse ! my kingdom for a horse, is from William Shakespeare, Richard III, part V 4.
In German they call the knight a Springer, a jumping animal, so let us invite writers here for quotations on this word.
In Hungary : a knight is a Hussar, what jokes can be made on that word ?
I wonder how many times chess players have uttered that famous saying in the history of the game: "A horse, a horse, my kingdom for a horse!"
Also, consider the fact that "One trick pony" could mean different things in chess, besides just doing one trick, it could indicate a tricky knight, or a tricked-out knight.
Just food for thought.