In gameplay terms, Vault 112 seems like a pretty decent energy producer that slows your opponents down, then becomes a powerful effect to spend your energy on, providing a free card which you can dig deeper for if you plug in some volts
Greens life gain is mostly either through sorceries (with the occasional instant) and creatures
Local Game Stores and Eternal-format organizers have effectively become the arbiters of whats acceptable in practice, not by law
Champions from Beyond feels like a dream for token brewers, letting you flood the board, scry, and eventually punch faces with a pseudo-Overrun
Recently Bank of America released a report about Hasbro, Wizards parent company, in which they stated, card prices are falling, game stores are losing money, collectors are liquidating, and large retailers are cutting orders. Lower profits for game stores means fewer game stores
These are intentionally not standard, and they are not meant to shuffle into your main deck