The special thing that identifies these cards, aside from the set symbol, are the special board art and the unique artwork reminiscent of children's storybooks
Open the Graves Open the Graves is a good example of the sort of mechanic that black token generators tend to have: When something dies, create something else (usually a zombie, who will probably die very, very soon)
If Kite hadn't activated the effect of his Galaxy Eyes Full Armor Photon Dragon, Yuma would have finally won against his rival
GameStop and Best Buy have one each, which means you're going to have to buy Journey Together products at both, and spend $30 or more between the two stores, if you want copies of each card
Customization is simple as the ramp shell is consistent enough to work without dragons if you want to take a more generalist approach
That holographic Machamp that came with the very first beginner decks, or the theme decks that came after