I protect the sheep in our society from the wolves.
In the Nocturne set there are Night Duration Cards such as Guardian and Ghost Town that can only be played during the Night Phase which comes after your Buy Phase. Our question is if you put a Night Duration Card in play during your Night Phase does it just stay in play for your next turn only and then it goes to the discard pile during the clean up phase or does the Duration card stay in play for two full turns of yours?
Does the card being in play during the Night Phase count as the first part of the Duration, then during your next full turn, then discard?
Duration cards stay in play until the Clean-up phase of the turn where they stop doing stuff. So if you play a Ghost Town, then it sets up an "At the start of your next turn" effect, which it sticks around for. That's the last thing it does, so in the Clean-up of that turn it gets discarded.
Crypt, on the other hand, stays in play for as long as it has Treasure cards underneath it. If you don't put anything in the Crypt, you discard it the same turn you play it. If you put one Treasure underneath it, then on your next turn you take that card and at the end of that turn you discard the Crypt. And so on.