Already in the Armory, made by Z. Link here
Hmmm. That is definitely a very similar mechanic. Guess thats what I get for not checking through armory first.
Slight difference on this one though. I made this affect cards in both the hand and the deck, and the duration is standard freeze duration.
The motivation for that is that it can be effective even when your opponent keeps an empty hand, but it is harder to pull off a full hand lockdown effect.
Both of those are important for balance I think.
Guess that will have to go into the discussion for the armory card then...