Feed the war machine

{1}{b}, Sacrifice a creature: You gain 1 life
and draw a card.
Long had it been forging in the dark
smithies of Mordor, and its hideous head,
founded of black steel, was shaped in the
likeness of a ravening wolf; on it spells of
ruin lay. Grond they named it, in memory
of the Hammer of the Underworld of old.