Before Yocun's Story
Dammen had risen through the rank to become a Maester of Yevon several years before Yocun became a Crusader. As Yocun grew through the ranks quickly, she worked closely with Dammen and considered him more of a friend rather than a superior, and would have chosen him as her guardian when she became a summoner if he had not been too occupied as Maester.
Maester Dammen organized a massive good luck celebration in the Calm Lands for Yocun and her guardians Barton and Silva before they began her journey. Yocun was more than just a little embarrassed by the fanfare, but her uplifting conversation with the Maester provided her with much-needed support.
When a sinspawn attacked the procession, Dammen argued with an adviser named Maldus, a man no one had ever seen before, on whether or not they should send in troops to help Yocun. Maldus won the argument and Yocun was not given reinforcements. Regardless, the sinspawn was taken out.
Later, after receiving the first aeon Shiva, the summoner party was attacked by Maldus and after a lengthy battle, convince a merchant named O'aka XX who had seen everything to travel to Bevelle and speak with Maester Dammen about the incident and report to them in Guadosalam. O'aka agreed.