In a fight, everyone is constantly watching for a chance to strike an enemy who is fleeing, distracted, or passing by. Such a strike is called an opportunity attack.
To make the opportunity attack, you use your reaction to make one melee attack against the provoking creature in two scenarios:
- Moving. You can make an opportunity attack when a hostile creature that you can see moves out of your reach. The attack occurs right before the creature leaves your reach.
- Rising from a Prone Position. A hostile creature who is getting up from a prone position within your reach will incur an opportunity attack before it can.
- Use an Object. Using an object while in a hostile creature’s reach will provoke an attack of opportunity as that action diverts attention away from threats in their immediate vicinity.
You can avoid provoking an opportunity attack by taking the Disengage action. You also don't provoke an opportunity attack when you teleport or when someone or something moves you without using your movement, action, or reaction.