From A Wiki of Ice and Fire
Wroth of the Dragonlords is a mummer's play written by Phario Forel. It is the first play Forel had ever written. In it, Prince Garin gives a speech on the eve of battle.
Izembaro, the King of the Mummers, quotes Prince Garin from this play the night he and his group of mummers are set to perform The Bloody Hand.
||It shall go ill for any man who fails me
quoting Prince Garin's line from the play