Well, while some of the Blue-Eyes support has been incredibly good (Blue-Eyes Alternative Dragon springs to mind as the epitome of incredible legacy support for the archetype), a lot of it is really bad or is completely and utterly useless in the current meta-game
While gold can be spent on packs and gems can buy entry into drafts and other events, wildcards are the only way to buy individual cards when deck building on Arena
Sephiroth, Fallen Hero is a recurrable threat or Commander in RW, which is a first for the color pair
Another effect is that once per turn, if you would tribute a monster(s) to activate a card or effect, you can tribute 1 dark monster your opponent controls as if you controlled it
The Japanese card market moves faster, with sets releasing several times per year and maintaining a steady flow of limited promotional releases tied to movies, events, and collaborations