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
At the start of your upkeep, Thopter Assembly will trigger, creating five 1/1 Thopter artifact creature tokens and bouncing Thopter assembly back to your hand
(Each deals damage equal to its power to the other.) Instant Tamiyo's Safekeeping Target permanent you control gains hexproof and indestructible until end of turn
Flayer of Loyalties Why make your own Eldrazi, when you can just make your opponents stuff into your own Eldrazi
What does surprise me is that Wizards of the Coast printed a three mana, colorless Planeswalker