Greater Mossdog | Magic: The Gathering
Formats Greater Mossdog is Legal in
Official Oracle Text for Greater Mossdog
Official Rulings for Greater Mossdog
6/7/2013 : Once you decide to replace a draw using a card's dredge ability, that card can't be removed from your graveyard "in response." (Replacement effects don't use the stack.)
6/7/2013 : You can't use dredge unless you're going to draw a card and the card with dredge is already in your graveyard.