Descent into Madness | Magic: The Gathering
Formats Descent into Madness is Legal in
Official Oracle Text for Descent into Madness
Official Rulings for Descent into Madness
5/1/2012 : First you choose the permanents and/or cards from your hand that will be exiled. Then each other player in turn order does the same. Then all the chosen permanents and cards are exiled simultaneously. Players who choose after you will know what permanents you'll be exiling when they choose. They'll know how many cards you'll be exiling from your hand, but they won't see those cards.
5/1/2012 : If there are more counters on Descent into Madness than the total number of permanents you control plus the number of cards in your hand, you'll exile all permanents you control (including Descent into Madness) and all cards from your hand.
5/1/2012 : If Descent into Madness isn't on the battlefield when its ability resolves, use the number of counters on it when it left the battlefield to determine how many permanents and/or cards from hands to exile.