How would that work in lieu of a full permanent area with no open slots?
Oh geez. I don't know if that's ever happened to me, it's so rare.
There are two ways I could see this going.
One, the new and useless permanent is destroyed. That's not too different to how the game would be affected anyway unless there's some Reverse Time that you'd use for permanents.
Two, the ability doesn't go through. Either you cannot target any more pillars or you just don't get a creature with the permanent's ability and you've wasted some quanta.
I'd opt for the second one. It seems 'safer' and a bit more in line with the way other full-field restrictions work ingame. Using Mitosis on a creature when you already have a full field, for instance.
If neither of those strikes your fancy, I suppose one might just decrease the counter of usable pillars/pendulums when this ability's used and add some kind of token on the card image to show there's a useless pillar there.
Anything else? If not, I'll go ahead and update the card so the upped version has a
cost instead of just one. Oh, and the card text rewording, too.
EDIT: Fixed it all.