By itself it hits for 1 damage, then 6, and then 8 over three turns, not to mention how stupid a second copy makes it
While the Pillar and Eidolon tend to be weaker in EDH overall, it seems to me that many of the favorite cards for the Urza decks are at 3 CMC or less making them perfect prey for these cards
Your opponents will quickly find themselves unable to compete
Drawing cards with your free spells is all kinds of silly, and its a good way to make up for the card disadvantage of having to exile a card from your hand to cast them for free
Honorable Mention: Ominous Harvest While Ominous Harvest does not have the mass appeal of the other cards on this list, I feel it is worth noting for the players who run multiplayer focused Cubes
Now tens of thousands of collectors from all over the world collect cards and sell them to each other