Gruesome Menagerie

Spectacle {4}{b}{b} (You may cast this spell for its spectacle cost rather than its mana cost if an opponent
lost life this turn.)
Trample
When This creature enters the battlefield, if its spectacle cost was paid, each player mills 2.
Gruesome Menagerie's power and toughness is
equal to the number of creature cards in all graveyards.