The deck jams in pretty much every town from Final Fantasy , minus one or two of the truly non-synergistic colorless lands
Zetalpa is keyword soup, and they're good keywords, but eight mana for a creature with no impactful abilities is rarely worth it
In addition to this, a big part of the reason these cards were so popular was because the mana in that Standard format was quite bad, to the extent that you were pretty close to wanting Attune with Aether in your decks even before the energy bonus, but once you have the energy bonus you might as well play Harnessed Lightning, which means you may as well play Rogue Refiner to power up your kill spell, and so on
Let's use something simple
In a plane where cute little animals wage some adorable wars, these cards dominate the battlefield
These are not okay These are cards that would probably be banned in Commander in a hypothetical world where all silver-bordered cards are legal