I like Chris' priority blockade and delayed blockade, though they are a bit formal.
I also like barricade, but unless you are looking in a dictionary, it's just another synonym for barrier, blockade, etc.
My favorite so far has been booby trap, and not just because it has "booby" in it.
If you're looking for less formal,
abandon = fence card (picture of a wooden fence)
blockade = wall card (current picture of brick wall)
I can't figure out how to put images in, so here's a url of what I made in MS Paint:
http://imgur.com/gallery/WQfmGKB/**Since I know citing your resources is always important, here's where I got the picture of the fence from:
http://www.123rf.com/clipart-vector/fence.html*EDIT: Another idea I just though of would be to call the abandon card the "Screen Card" but I can't picture a suitable way to illustrate a screen off the top of my head
Edited 9/2/2015 01:45:24