12/1/2004: Crucible of Worlds allows you to play land cards from your graveyard as well as from your hand.
12/1/2004: Crucible of Worlds doesn't change the times when you can play those land cards. You can still play only one land per turn, and only during your main phase when you have priority and the stack is empty.
12/1/2004: Crucible of Worlds doesn't allow you to play activated abilities (such as cycling) of land cards in your graveyard.