You're right about it needing to be a spell, kinda got that mixed up. I'm saying the card would duplicate that actual condition of the targetted shield, kinda like parallel universe duplicates the condition of the targetted creature, so that chaining phase shields together wouldn't work, but you could copy a sweet bone wall!
So I think i'm done messing with this, the saved card files are attached previously, I think this card could make it into the game easily, i has what 95% of the other cards here don't, simplicity, which goes a long way it seems.
So yea, anyone feel free to take this and edit it and run with it, make it your own, I declare Duplicate Open Source!
John