Well, I found It can be both
Then came Shandalar, where we could download the cards with a low-quality screenshot, print it out with an inkjet printer, stick it on a useless piece of land, such as an ancient tomb, and play
Eldrazi Conscription gives a cool +1/+1 and annihilator 2
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
I find that, typically, when you are about to off an Oblivion Stone or a Nevinyrral's Disk effect, at least one other player wants it