Toughness

Toughness is a characteristic that only creatures have. The number after the slash printed on the lower right corner of a creature card is its toughness. See rule 208, "Power/Toughness." A creature that's been dealt damage greater than or equal to its toughness (and greater than 0) has been dealt lethal damage and is destroyed. This is a state-based effect; see rule 420. Some creature cards have toughness represented by * instead of a number. The object has a characteristic-defining ability that sets its toughness according to some stated condition. This ability functions everywhere, even outside the game. A noncreature permanent has no toughness, even if it's a card with a toughness printed on it (such as a Licid that's become an Aura).