Kozmos dominated YCS San Jose thanks to their latest batch of support from Dimension of Chaos. Although the November Forbidden & Limited List didn't take effect until after the event, Kozmos had no problem defeating Nekroz, Qliphorts, Burning Abyss, and Shaddolls as duelists like Jessy Samek climbed to the top tables, who ultimately won the event with his teched-out version of Kozmos.
Samek's opponent in the final round, Sebastian Crawford, played an almost entirely different trap line-up and designed his build to feature Light and Darkness Dragon. Samek focused more of his support around the new Kozmo Dark Destroyer, banking on his opponent's inability to consistently destroy it.
The new face of the Kozmos strategy is Kozmo Dark Destroyer – its massive 3000 ATK, replacement effect, monster removal, and targeting immunity should warrant a high-cost Summoning condition. Instead, you can Special Summon Dark Destroyer from your hand through the effects of Kozmo Farmgirl, Kozmo Strawman, Kozmo Goodwitch, or Kozmoll Wickedwitch, and Samek played three copies of Reasoning for even more Special Summoning power. With so many different Levels of monsters in his deck, his opponents would rarely call Reasoning right. He also played two copies of Escape from the Dark Dimension, which he could activate to Special Summon a banished Dark Destroyer or Wickedwitch.
Samek sided two Cyber Dragon Core to deal with his opponent's Dark Destroyers. Core becomes 'Cyber Dragon' while on the field or in the graveyard, so you can use it along with your opponent's Machines to Special Summon Chimeratech Fortress Dragon. When one copy of Core hits the graveyard, Samek could banish it from his graveyard to Summon his second Core from the deck. Since Core's effect searches out a Cyber spell or trap, Samek also sided Cyber Network to Summon back his banished Kozmo Slipriders and Kozmo Forerunners.
Kozmos became the deck to beat in the final days of the last format, even before their competition was knocked down a peg. Time will tell how they'll handle the spotlight, and to what extremes players will go to get an edge in the match-up.