Misthollow Griffin

• WWizards of the Coast2012-05-01
  Official Ruling
  You must still pay Misthollow Griffin's mana cost when you cast it from exile.
• WWizards of the Coast2012-05-01
  Official Ruling
  Misthollow Griffin's ability doesn't change when you can cast creature spells: when you have priority during your main phase when the stack is empty.
• WWizards of the Coast2012-05-01
  Official Ruling
  Misthollow Griffin doesn't have an ability that exiles itself. Some other effect will be needed to get the card into exile.
• WWizards of the Coast2012-05-01
  Official Ruling
  Misthollow Griffin can also be cast from a player's hand.

Rulings via Scryfall