Conditions alter a creature’s capabilities in a variety of ways and can arise as a result of a spell, a class feature, a monster's attack, or other effect. Most conditions, such as blinded, are impairments, but a few, such as invisible, can be advantageous.
A condition lasts either until it is countered (the prone condition is countered by standing up, for example) or for a duration specified by the effect that imposed the condition.
If multiple effects impose the same condition on a creature, each instance of the condition has its own duration, but the condition’s effects don’t get worse.
A creature either has a condition or doesn’t. The following definitions specify what happens to a creature while it is subjected to a condition.
A grappled creature’s speed becomes 0, and it can’t benefit from any bonus to its speed.
The condition ends if the grappler is incapacitated (see the condition).
The condition also ends if an effect removes the grappled creature from the reach of the grappler or grappling effect, such as when a creature is hurled away by the thunderwave spell.
An invisible creature is impossible to see without the aid of magic or a special sense. For the purpose of hiding, the creature is heavily obscured. The creature’s location can be detected by any noise it makes or any tracks it leaves.
Attack rolls against the creature have disadvantage, and the creature’s attack rolls have advantage.
A petrified creature is transformed, along with any nonmagical object it is wearing or carrying, into a solid inanimate substance (usually stone). Its weight increases by a factor of ten, and it ceases aging.
The creature is incapacitated (see the condition), can’t move or speak, and is unaware of its surroundings.
Attack rolls against the creature have advantage.
The creature automatically fails Strength and Dexterity saving throws.
The creature has resistance to all damage.
The creature is immune to poison and disease, although a poison or disease already in its system is suspended, not neutralized.
