Greed Island arc
After attending the meeting of different teams organized by Kazsule, Montreux and his teammate Yabibi become part of the group of 15 players who enter Razor's gym to challenge him and his subordinates for the Patch of Shore card. He volunteers to fight in the first match against a Boxer, who happens to be an Emitter like him. Despite landing a number of punches, he receives a powerful uppercut in the jaw at the same time and is knocked unconscious, thus losing the match. Not long after leaving the gym, he and Yabibi are killed by the Bomb Devils.
Abilities & Powers
Montreux is moderately perceptive, realizing the boxer pirate was an Emitter because the ring was ideal for this type of Nen users. He managed to briefly have the upper hand against his opponent, though he was eventually knocked out in one blow.
Montreux is an Emitter. His Hatsu allows him to send aura projectiles about the size of his fist flying at the opponent by punching the air. Said projectiles are rather fast and powerful, leaving a bruise/scorch mark just by brushing past the pirate boxer's shoulder.