Miquelot de Prades
Gonzalo Fernández de Oviedo y Valdés, in his work Las Quinquagenas de la nobility de España,  spoke of a Catalan soldier (Michalot de Pradas) who roamed Italy, winning all the duels with a sure thrust to the opponent's neck. Repentant of his life, that soldier went to take refuge in the monastery of Montserrat. One bad day an Italian soldier with two swords showed up and challenged Miquelot (saying that he wanted to see the secret thrust, claiming that he would know how to counter it). Miquelot flatly refused to fight but the other's insistence forced him to do so. The Italian ended up dead, with a thrust to the neck. There was probably no better way to teach it. Repentant of the new death, he went to Rome to ask for forgiveness. The pope incorporated him into his troops.