If you'd like to read more about how we design for Universes Beyond in general, check out Mark Rosewater's article
Whats your favorite cascade card
Lutri, the Spellchaser Its hard to have a card banned in Commander at the top of this list, so Lutri, the Spellchaser chills at number two
Vesuvan Duplimancy If youre like me, you probably also thought this was Vesuvian Diplomancy, but no, its Vesuvan Duplimancy
Its definitely worth bearing in mind that these cards are also an awful lot cheaper than the official versions so, if you dont mind the fact that they arent original cards (as well as being able to deal with the fact that quality may be inconsistent depending on the card and its seller), its certainly a lot more cost effective to buy the far more common, unofficial metal cards!