Different Dimension Demons, or D/D/D (also D/D), is a relatively new theme that's only just started to find its way into the TCG. It's surprisingly competitive in its current state despite missing nearly half of its support. As evidence of that, Jackson Smith placed 9th at the Regional in San Antonio Texas with his – admittedly untested prior to the event – build of D/Ds. Winning against a field of Magician Pendulums, Kozmos, Majespecters, and Performage Pendulums is no small feat. It's a great example of the untapped potential this theme has, especially given its relatively simple OTK setups.
Dark Contract Continuous Spell and Trap cards make up the backbone of this strategy, particularly the search card Dark Contract with the Gate. To get to Gate as early as possible, Smith played three copies of D/D Savant Kepler and a copy of One for One to Special Summon it from the deck. Additionally, he could search Kepler or either of his other Pendulum D/D/D monsters by resolving Wavering Eyes. Against a field of primarily Pendulum strategies his two Wavering Eyes in his Main Deck ended up being relevant more often than not. Smith could also side in a third copy when he was sure he wasn't matched up against a non-Pendulum strategy.
Transmodify is another highlight here, turning D/D/D Oracle King d'Arc into D/D/D Oblivion King Abyss Ragnarok. When Ragnarok hits the field its effect would Special Summon D'Arc from the graveyard, putting a total of 5000 ATK on the board. Alternatively, Smith could instead Special Summon a second copy of Ragnarok from the graveyard, then overlay for D/D/D Duo-Dawn King Kali Yuga, which would disable all other effects until the End Phase. Kali Yuga's effect includes a Heavy Storm that can be activated on either player's turn. It's a nightmare for Pendulum strategies to deal with. Smith could OTK on a moment's notice, play any Virus trap, and sided into Mask Change II to put Masked HERO Dark Law on the field. Different Dimension Demons are really cool; give them a shot and they might just surprise you.