D / D " D / D " ( " DīDī " ) , known as DD in the English manga and pronounced " Double D " in the dubbed anime , is an archetype of primarily DARK Fiend monsters used by Declan Akaba in the " Yu - Gi - Oh ! ARC - V " anime and manga . It is supported by its own sub - archetype ; " D / D / D " . Design . Appearance . The regular " D / D " monsters seem to be based on different figures and monsters from Western mythology , while the " D / D Savant " monsters are references to great natural scientists from Western history . In contrast , the " D / D / D " sub - archetype features a distinct design style from the rest of the archetype , with many of its members modeled after famous conquerors from world history . Taken together with its subordinate and sub - archetypes , the " D / D " archetype features a mild " business " sub - theme ( probably to fit the profession of their owner in the anime ) , with many support cards referencing elements of modern big business . For example , the " Dark Contract " cards resemble business contracts , and the names of " D / D / D Human Resources " and " Contract Laundering " reference . Additionally , some of the archetype ' s boss monsters such as " D / D / D Doom King Armageddon " feature a pun in its Japanese name , such as " " Great Des ( Death ) King " " being scripted as " " Shiiō " " , a homophone for " " . A similar pun can be found in the Japanese name of " D / D / D Oblivion King Abyss Ragnarok " / " D / D / D Wave Oblivion King Caesar Ragnarok " , " " Oblivion King " " , which is scripted as " " Kaichiō " " , a homophone for " " . So far in the ARC - V manga , the " D / D " monsters appear to be demons with a mechanical , scientific theme ( distinct in design to the " D / D Savant " monsters ) and have equipment like scales or microscopes instead of faces . Etymology . According to Sora Perse , " D / D " is short for " Different Dimension " ( ディファレント ・ ディメンション " Difarento Dimenshon " ) , the same as the " D . D . " series . Playing style . Anime . This archetype ' s primary play - style is to use the beneficial effects of the " D / D Savant " monsters and " Dark Contract " Continuous Spells and Traps to gain card advantage : while trying to avoid the LP damage with the Field effects of " D / D / D Oracle King d ' Arc " , " D / D / D Rebel King Leonidas " or remove the " Dark Contract " cards from the field ( after completing the card ' s combo ) with the Self Reviving effect of " D / D Lamia " . When Normal Summoned " D / D Savant Kepler " can search for any " Dark Contract " card , " D / D Swirl Slime " has a useful effect , from the hand , for loading the Graveyard for revival targets for later and can Banish itself from the Graveyard , on the same turn , Special Summon any " D / D " Monster from the Hand . The Monster Cards " D / D Savant Copernicus " and " D / D Necro Slime " can be searched by the effect of " Dark Contract with the Gate " and both have effects that allow themselves and other D / D to be used as Fusion Material to Summon the Level 6 usually first " D / D / D Flame King Genghis " , Level 7 Panic Button " D / D / D Oracle King d ' Arc " and Level 8 beater / rank 8 fodder " D / D / D Dragonbane King Beowulf " . " Genghis " can be used as Synchro Material for " D / D / D Gust King Alexander " with " D / D Lamia " ; these three Monsters can now revive each and be used for two of the most powerful Synchro Monsters called " Crystal Wing Synchro Dragon " , " D / D / D Cursed King Siegfried " and sometimes " PSY - Framelord Omega " . Both " Abyss Ragnarok " and " Kepler " are recoverable with the Pendulum Effect of " D / D Savant Thomas " , and the Monster Effect of " Thomas " is the simplest way to search for a Level 8 " D / D / D " Monster and make " D / D / D Duo - Dawn King Kali Yuga " . " Caesar " and " d ' Arc " were also one of the earliest " TCG " ( before " Alexander " and " Genghis " were released ) combinations used to abuse the recovery effect of " d ' Arc " and the effect of " Caesar " to add a " Dark Contract " card from the Main Deck to the hand . Additionally , the Deck has access to many cards that can recycle resources from the Graveyard , face - up from the Extra Deck , and the Pendulum Zone s , such as " D / D Lilith " , " D / D / D Oblivion King Abyss Ragnarok " and " D / D / D Human Resources " , which requires the player to carefully utilize resources from many different regions of the field . The " D / D / D " archetype is a sub - archetype to the " D / D " , and consist of more powerful monsters , including Fusion , Synchro , Xyz , and Pendulum Monster s . The " D / D " monsters are used to facilitate the Summons of the " D / D / D " monsters . Examples are " D / D Nighthowl " and " D / D Berfomet " , which make Synchro and Xyz Summon ing much easier by Summoning the required Material from the Graveyard and manipulating the Materials ' Levels , respectively . Similar to the field effect of " Thomas " : " D / D Berfomet " can change the Level of a " D / D " monster to anywhere from 1 - 8 , but restricts Special Summoning to Monsters from this archetype . The only Xyz Monster s for this effect are " Duo - Dawn " , " D / D / D Wave King Caesar " or D / D / D Marksman King Tell . With the release of " " , " D / D Savant Copernicus " and " D / D Savant Newton " provide more consistent Pendulum Scales than " D / D Savant Kepler " and " D / D Savant Galilei " . " Copernicus " has the bonus of dumping " D / D " cards from the Deck to start combos , whereas Newton can discard itself to add a " Dark Contract " card or a different " D / D " monster from the Graveyard . " D / D Orthros " is a reusable Tuner monster , by virtue of also being a Pendulum Monster , to make Synchro Summons easier to execute . " Dark Contract with the Yamimakai " can set the Pendulum Scales from the Graveyard or Extra Deck to start Pendulum Summoning . Manga . In the manga , " D / D " has a vastly different play - style . Unlike its anime counterpart , it doesn ' t focus on Fusion / Synchro / Xyz Summoning or negating effect damage from the " Dark Contract " cards . Instead , it focuses on reducing the DEF of the opponent ' s monsters to 0 ( reflecting Reiji ' s obsession with the number zero in the manga ) and dealing piercing damage . However , it does make use of Pendulum Summoning . Weaknesses . Because this Deck focuses on swarming to push the game , cards that can disable or counter swarming or searching , like " Fossil Dyna Pachycephalo " or " Thunder King Rai - Oh " , can greatly hinder this Deck . Additionally , the archetype ' s synergy with the " Dark Contract " archetype provides a weakness to Spell / Trap removal , as well as a dependence on cards that mitigate the damage from the " Dark Contract " cards . Official Decks . The following Decklists may or may not contain copies of cards that exceed the maximum amount allowed by the current Forbidden & Limited List . These should not be changed , as these Decklists are copied verbatim at the time they were published .