D/D/D

"DDD" ( DīDīDī) is an sub-archetype of "DD" archetype used by Reiji Akaba in the special Yu-Gi-Oh! ARC-V chapter and anime.

Design
So far, every "DDD" Monster has been named after a historical military leader, except "DDD Infernal Armageddon the Great Des Lord" which is named after an event.

Etymology
According to Reiji Akaba, "DDD" is short for "Different Dimension Daemon" (ディファレント・ディメンション・デーモン Difarento Dimenshon Dēmon). However, it doesn't make part of the Archfiend, because the Japanese デーモン (Daemon) is not explicitely written.