Just noticed something weird.
Before the black wall is a plot that says "When revealed, name a challenge type. In order to declare any characters to attack or defend during challenge of that type, a player must declare all of his or her eligible characters. Then, if this is your revealed plot card, trigger the 'when revealed' effect of the top River plot card in your used pile. " it doesn't tell any time of when the effect would end (end of round/phase). Is this effect passive or constant? and how does it actually work since it is lacking the timing information? can I trigger the effect with another river plot or not?