So let’s set the scene. You’re currently in a battle against a mage. You are losing. Your party members are useless and you’re looking for a way to turn the tide. The mage is casting a spell and you are right beside them.

An idea comes to you! You can use this moment whereupon the mage is casting a spell to provoke an attack of opportunity! But here’s the thing – the DM says no! A classic D&D argument erupts and you find yourself trawling through the rules to try and find an answer.

If you don’t have a rules lawyer that knows everything there is to know about 5e, it can be difficult to work out. The real question is whether or not casting a spell provokes an attack of opportunity!

If you’re looking for the answer to this question for your 5e game, then you’ve come to the right place! We’re going to be taking you through everything to do with attacks of opportunities in D&D, when they can occur and whether or not a spell provokes one.

We have also included an extensive FAQ section that will take you through some other rules and concepts around this issue, just in case you still have some questions left over by the end of our article!

So let’s open the rules book and work this one out!

What Is An Attack Of Opportunity?

The most important thing when hashing out rules disputes is first defining the rules. Let’s begin with the concept of an ‘attack of opportunity.’

An attack of opportunity occurs when a creature makes a melee weapon attack against another creature that has not yet acted or reacted to your action but could have. The attacker must make this choice before the roll for the attack is made. If the target can take only one reaction, it takes the same reaction it would if it had been targeted by your action.

For example, if you use your action to push a creature 5 feet away from you, you don’t provoke an attack of opportunity from that creature because it hasn’t taken any actions yet. However, if you use your action to shove a creature into a square occupied by a hostile creature, then you do provoke attacks of opportunity from both creatures.

The Attack Of Opportunity Reaction

When you choose to take an attack of opportunity, you get one free attack at advantage on your next turn. This attack cannot be chosen as part of the same attack of opportunity. It must be chosen separately.

You may re-roll the attack of opportunity after using it once. After you use an attack of opportunity, the attacker gets a new attack of opportunity against you.

Attack Of Opportunity Vs Spells

Spells cast directly affect a creature without provoking an attack of opportunity. Spells cast indirectly affect a creature that is within range (as defined in chapter 7) of the caster.

A spell cast directly affects a creature without provoking an attack of opportunity. A spell cast indirectly affects a creature that is within the range of the spell.

A spell cast directly affects a target that doesn’t provoke an attack of opportunity. A spell cast indirectly affects a target that does provoke an attack of opportunity, but only if the target was within the range of the caster.

When Casting A Spell Provokes An Attack of Opportunity

There are two ways that spells can provoke an attack of opportunity:

  1. The spell itself states that it causes an effect that requires an attack of opportunity. For instance, the fireball spell states “Each creature in a 20-foot radius burst must succeed on a Dexterity saving throw or take fire damage equal to half the amount rolled.”
  2. The spell description includes language such as “if the target is within 5 feet of you” or “the target must succeed on a Constitution saving throw or become stunned until the start of your next turn.”

In these cases, the spell casts an indirect effect that targets a creature that might otherwise provoke an attack of opportunity (such as a creature standing near you). You still need to decide whether to use your action to take the attack of opportunity.

If you decide to use your action to provoke an attack of opportunity with the spell, the attacker gets a chance to respond. If they fail they’re save, they suffer the effects of the spell.

If you decide not to use your action to cause an attack of opportunity, no attack of opportunity is provoked.
Casting a spell that provokes an attack of opportunity does not give you an advantage on the attack.

Example 1: Fireball

Fireball says “each creature in a 20 ft. radius burst must succeed on dexterity saving throw or take fire dmg equal to half the amount of the roll”

This spell creates an area of effect that forces a creature to make a dexterity saving throw every time it enters the area.

Since this is an area of effect spell, it will always create an attack of opportunity for creatures that enter its area. However, since the spell specifies that it deals damage based on the number rolled on the dice, there’s no way to know how much damage the spell will deal before casting it.

So when deciding whether to use your action or not, you have to consider what kind of damage the spell could do. If the spell deals 3d6+5 damage, then you would want to use your action to attempt to provoke an attack of opportunity. Otherwise, you wouldn’t want to waste your action trying to provoke an attack of opportunity.

Example 2: Shocking Grasp

Shocking grasp says “the target takes 4d8 lightning damage”

This spell has a very specific effect. It deals damage based on the total rolled on the d20. So if you roll a 12, the target takes 24 damage. This means that there’s no way to tell how much damage this spell will deal before casting.

Because of this, you should never try to provoke an attack of opportunities with this spell. Even if the target is within 5ft of you, they won’t be able to react fast enough to avoid taking the full damage from the spell.

Note: There are some exceptions to this rule. Spells like Thunderwave say “The thunder wave spell creates a 60-foot cone of sound centered on a point you choose within range. Each creature in the area must make a DC 15 Wisdom saving throw.”

In this case, the spell doesn’t specify any damage at all. Instead, the spell just creates an area of effect where a creature must make a wisdom saving throw. Since this is an area of effect spell, it will always trigger an attack of opportunity for anyone who enters the area.

House Rules

Okay so you’ve hashed out the rules together, but your DM is still not happy. Well here is where you can begin to create house rules. Perhaps you’re a DM yourself and you want to bend and change the rules of 5e a little bit. That’s fine and common practice.

House rules are simply changes made by a DM to the rules as written. They don’t necessarily need to follow the letter of the law, but they should follow the spirit of the game. The most important thing about house rules is that they shouldn’t break the balance of the game.

For example, let’s look at the two spells mentioned above. Both spells were designed to work differently than other spells. But both also have similar effects. And while one may be more powerful (and thus better) than the other, neither breaks the balance of the game because they both fulfill a similar purpose.

The main focus as a DM of any game is to make sure that your party is having fun and experiencing your story – so if you need to bend things from time to time, that’s fine!

Final Thoughts

So there you have it! Attacks of Opportunities are a great rule within 5e that can cause a lot of twists and turns within your battle. However, they aren’t perfect. You’ll find that sometimes you’ll get stuck between a rock and a hard place when using them.

Sometimes you’ll get attacked even though you didn’t provoke an attack of opportunity. Other times, you’ll miss out on attacks of opportunity because you used up your actions.

However, these are minor problems that can easily be solved through house ruling. Dungeons and Dragons is a complex game, and from time to time these issues can come up. The most important thing is that you keep the game going and make sure that it’s fun for everyone!

We hope that this article has given you everything you need to know about this issue, if not, check below for our FAQ section which will aim to answer any additional questions you might have!

Frequently Asked Questions

Get your last-minute questions answered here!

What Classifies As An Attack Action?

An attack action is defined as anything that requires you to use your reaction. For example, if you cast a spell or take the Dash action, then you would use your reaction to do so. If you move 10ft, then you would use a movement action. If you hit someone with a melee weapon, then you would use an attack action.

As long as you use your reaction to perform the action, then it counts as an attack action.

How Often Does An Attack Of Opportunity Occur?

Attack of opportunity occurs every round.

Can I Provoke An Attack Of Opportunity With My Spell?

No. As stated earlier, spells cannot provoke an attack of opportunity unless they specifically state that they do.

What Is A Special Action?

A special action is an action that only works once per turn. Examples include casting a spell, making an ability check, moving, taking the Dash action, etc.

What Is A Touch Attack Spell?

A touch attack spell is a spell that deals damage based on how close you are to the target. These spells usually require a ranged weapon.

Is There A Difference Between A Standard Action And A Swift Action?

Yes. A standard action is something that takes 1 minute to complete. It includes everything except for a bonus action. A swift action is something that takes less than 1 minute to complete. This includes any bonus action.

If I’m Holding A Shield, Can I Use My Action To Attack With It?

Yes. When you hold a shield, you can use your action to melee attack with it.

Do I Have To Declare What Kind Of Attack I Am Going To Use Before I Make The Attack?

You don’t have to declare what type of attack you’re going to use until after you’ve made the attack. So, for example, if you want to attack with a dagger, you could just say “I’m attacking with a dagger” without declaring what kind of attack you’re doing. Once you’ve declared your attack, you must specify which type of attack you’re doing (i.e., a melee attack).

If I’m Wielding A Melee Weapon, Can I Use My Reaction To Strike Another Creature?

You can use your reaction to strike another creature if you meet all three criteria:
You can reach the target.
Your target is adjacent to you.
You haven’t already taken a bonus action this combat.