George R.r. Martin said this quote

It was a cruel fate, Yet not so cruel as Mago's will be. I promise you that, by the old gods and the new, by the lamb god and the horse god and every god that lives. I swear by the Mother of Mountains and the Womb of the World. Before I am done with them, Mago and Ko Jhaqo will plead for the mercy they showed Eroeh.