as long as pact weapon is attached to a creature, you don't lose the game for having 0 or less life.
whenever equipped creature attacks, draw a card and reveal it. the creature gets +x/+x until end of turn and you lose x life, where x is that card's mana value.
equip—discard a card.
The Night Serpent tasted the warlock's ambition and savored the dark hunger in her soul.