The general party size is four--so we wanted to provide enough cards for each player. Thirteen multiplied by four is 52 which is a full deck and standard size. This meant that one condition had to cross the threshold and live in another deck. Prone cordially volunteered and was an obvious choice to provide in the combat deck. Thanks, prone.
Although the descriptions are similar, we adjusted the shipping levels in order to allow more people the ability to pledge over all. The way kickstarter works is that it doesn't allow removal of a tier once a pledge is made. Other than that, they are the same--so go for the available tier with updated shipping :)
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