While many Duelists use "Archfiend" cards in the anime and manga as a result, only Titan and Raizo Akuma runs dedicated Decks
In the anime, this card was technically a fusion, synchro, XYZ, effect monster, and pendulum monster, all wrapped into one
Kelly started fleshing out what stories those would be, so Set Design could build Sagas that mechanically fit the story that wanted to be told
The rapidly accumulating card advantage alongside dealing extra damage each time a ninja you control connects in combat can quickly snowball games, especially when a 1-drop gets through unchecked on turn 2
You can draw most of your deck with Ad Nauseam, use Lion's Eye Diamond alongside Underworld Breach to generate loads of mana to recast cards from your graveyard, and use the rest of your cards in your graveyard to draw out your deck that way