Can be used when you have 3 trap cards in the Graveyard. 1 random Trap Card in your Graveyard is added to your hand. Then, shuffle 1 random Trap Card in your Graveyard into your Deck. This skill can only be used once per Duel.
Chain Reaction is the only useful
This skill provides advantage to the deck that depends on Trap cards and effect damage although there are not many trap cards that could inflict effect damage in the current card pool.
When equipped with this skill, it is suggested that player includes “Attack and Receive” of 3 copies into the deck. As normally; without this skill, the activation of 3 copies would deal total damage of 3000 damage to the opponent’s Life Points. However, under the effect of Chain Trap skill, it would deal 3600 damage. If the opponent’s deck did not include any Life Points recovery cards, it would take 2 more activation of your trap cards to finish the duel. → Chain Reaction: deck recipe
Odion is the servant of the Ishtar family and has sworn his allegiance to Marik. An honest Duelist who Duels fair and square, his Deck is comprised of Trap Monsters, such as "Embodiment of Apophis," to ensnare his unsuspecting opponents.
Has anyone tried to win 100 times or so against Odion while playing as Joey? Maybe that's the way to unlock Yami Marik :P
I know, it's most likely not, but he has this line of dialogue when losing against Joey where he says that he can't hold Marik's evil side back any longer. I think this would be a cool hidden mission, but it sadly doesn't work with what Bakura said about YM during his event...