You can't cast more than one spell each turn.
You may play cards from your graveyard.
If a card would be put into your graveyard from anywhere, exile it instead.
10/4/2004 The cards in your graveyard are not considered to be in your hand for any reason. For example, you can’t discard them.
10/4/2004 You count spells that were cast this turn before this card enters the battlefield. (The Invasion FAQ is not correct on this point.)
10/4/2004 It will exile itself if it is going to the graveyard from the battlefield.