Most members of the Poku Saeruo Degonjo who are warriors will eventually come up with a Boqatsou, meaning Curse of Death or Death Curse. It is pronounced (bōkhăt-sōū). It is something that a warrior develops out over time; in fact it is not uncommon for the Death Curse to evolve as the warrior evolves. It is a phrase that they will say to defy death, and possibly to make their enemy hesitate. Most Death Curses begin with a fairly simple phrase, and as the warrior gains experience and faces various dangers, they modify the phrase.
Note: It is not necessary to have a Boqatsou, but having one adds to the flavor of your character.