Three cards have been confirmed by the official Twitter to be in the Deck, and most are designed to take advantage of Lair of Darkness or the Virus Cards.
SR06-JP008 Caius the Mega Monarch
Level 8 DARK Fiend Effect Monster
ATK 2800
DEF 1000
You can Tribute Summon this card by Tributing 1 Tribute Summoned monster. If this card is Tribute Summoned: Target 1 card on the field; banish it, and if you do, inflict 1000 damage to your opponent, then, if it is a DARK Monster Card, banish all cards with that name from the hand, Main Deck, Extra Deck, and Graveyard of the player who controlled it. If this card was Tribute Summoned by Tributing a DARK monster, add this additional effect.
● You can target 2 cards, instead.
Level 1 DARK Fiend Effect Monster
ATK 300
DEF 200
If this card is Tributed: Draw 1 card. If a monster you control would be destroyed by battle, you can banish this card from your Graveyard instead.
SR06-JP026 Foolish Burial Goods
Normal Spell Card
Send 1 Spell/Trap Card from your Deck to the Graveyard. You can only activate 1 “Foolish Burial Goods” per turn.