They can only take one or two hits each and aren't very good for attacking (or 'Challenging') your opponent's cards, but they cost a mere one Ink to deploy, meaning you can drop them on turn one
That may not seem like much but if the opponent is unable to take Calhoun out in one strike, that resist +1 may effectively double her health
a little slow and costly, but 3 mana to exile anything does work, even if your opponents can get it back
Another difference was that invitations to the World Championship could not be gained through Pro Tour Qualifiers
Imagine two Overlord of the Mistmoors rampaging across the board or twice as many Mind's Dilation triggers
There's also the tiny problem of this costing seven mana, all of it colored, but the combination of both winning the long game and keeping you alive to see it makes seven feel cheap, and there's enough behind this card that there is no need to worry about following it up with another copy unless your opponent can fire one back at you