To do the following, you will need two Nintendo DS systems and Yu-Gi-Oh! Nightmare Troubadour or Yu-Gi-Oh! GX Spirit Caller. Make a wireless connection chatroom in Yu-Gi-Oh! Duel Monsters: World Championship 2007 on the first Nintendo DS. Then, join the chatroom through Yu-Gi-Oh! Nightmare Troubadour or Yu-Gi-Oh! GX Spirit Caller on the second Nintendo DS. If you joined the chatroom with Yu-Gi-Oh! Nightmare Troubadour, you will unlock Joey, Kaiba, Yami Marik, Yami Yugi, and Yugi Duelist; Stuffy Collared Shirt (clothes, male) and Pink Suit (clothes, female); and Cheap Disk (disk, male and female). If you joined the chatroom with Yu-Gi-Oh! GX Spirit Caller, you will unlock Alexis, Aster, Dark Zane, Chazz, and Jaden Duelist; Slifer Red Jacket (clothes, male) and Obelisk Blue Uniform (clothes, female); and Alchemy Disk (disk, male and female). Note: Kaiba, Yami Marik, and Yami Yugi have God cards.