These cards do not handle well. They are clumpy. They are even hard to get back into the box (on
account of the protruding inner bottom flap). The marking system is supposedly explained on their
website, but the link provided does not give you access. You will find the marking system explained
in rudimentary terms on kickstarter. It is just a one-way marker, but even with the aid of a
magnifying glass I cannot detect it.