Secret Lesson 11
Bonus Actions, Reactions, Triggers, and Timing
You now understand the game's standard Actions.
But a creature's turn can sometimes include more than its normal action.
Certain class features, spells, and other rules can give you access to another type of activity called a:
BONUS ACTION
And some rules allow you to respond immediately to something that happens through a:
REACTION
These are separate from your normal action.
Understanding the difference between:
Action
Bonus Action
and
Reaction
is essential for understanding combat timing.
THE THREE MAIN ACTION TYPES
A useful starting point is:
ACTION
The main thing you do on your turn.
Examples include:
-
Attack
-
Dash
-
Dodge
-
Magic
-
Search
-
Ready
BONUS ACTION
An additional special action that is available only when a rule specifically gives you one.
REACTION
An immediate response to a particular trigger.
A Reaction can happen:
-
on your turn
-
on another creature's turn
depending on when its trigger occurs.
BONUS ACTIONS
A Bonus Action is an additional type of action that certain:
-
class features
-
spells
-
abilities
-
other game rules
allow you to take on your turn.
The most important rule is this:
YOU DO NOT AUTOMATICALLY HAVE A BONUS ACTION
A Bonus Action is available only if a specific rule says that you can do something as a Bonus Action.
YOU CANNOT INVENT A BONUS ACTION
Suppose your character has no feature or spell that uses a Bonus Action.
You cannot simply say:
“I use my Bonus Action to attack again.”
There must be a rule that gives you something you can do as a Bonus Action.
Without such a rule:
THERE IS NO BONUS ACTION AVAILABLE TO TAKE
EXAMPLE — CLASS FEATURE
The SRD gives the Rogue's Cunning Action as an example of a feature that allows a Bonus Action.
The exact Cunning Action rules will be covered when we study the Rogue.
For now, the important idea is:
the class feature creates the Bonus Action option.
ONE BONUS ACTION PER TURN
Even if you have several different Bonus Action options available:
YOU CAN TAKE ONLY ONE BONUS ACTION ON YOUR TURN
EXAMPLE
Suppose your character has three abilities:
Ability A — Bonus Action
Ability B — Bonus Action
Ability C — Bonus Action
You cannot use all three on the same turn.
You must choose:
ONE
BONUS ACTIONS DO NOT REPLACE YOUR NORMAL ACTION
A Bonus Action is separate from your standard action.
For example, if a feature permits it, your turn might include:
Action — Attack
and:
Bonus Action — use a class feature
These are different parts of the turn.
YOU CHOOSE WHEN TO TAKE YOUR BONUS ACTION
Unless the rule gives the Bonus Action a specific timing requirement, you decide when during your turn to use it.
For example, depending on the rules involved, you might use your Bonus Action:
before your action
or:
after your action
or between other permitted parts of your turn.
SPECIFIC TIMING OVERRIDES YOUR CHOICE
If the Bonus Action's rule specifies exactly when it can occur:
FOLLOW THAT TIMING
For example, imagine a hypothetical feature says:
“Immediately after you take the Attack action, you can use a Bonus Action to…”
You could not use that Bonus Action before taking the Attack action.
The specific timing requirement controls when it becomes available.
This follows the rule you learned in Lesson 2:
SPECIFIC RULES OVERRIDE GENERAL RULES
LOSING THE ABILITY TO TAKE ACTIONS ALSO PREVENTS BONUS ACTIONS
The SRD states that anything that prevents you from taking actions also prevents you from taking a Bonus Action.
This is important because certain conditions can remove your ability to act.
For example, the Incapacitated condition prevents a creature from taking:
-
Actions
-
Bonus Actions
-
Reactions
BONUS ACTION QUICK RULE
Remember:
Do I have a rule that gives me a Bonus Action?
NO
You cannot take one.
YES
You can choose one Bonus Action option.
You can take:
ONLY ONE PER TURN
REACTIONS
A Reaction is different.
A Reaction is an immediate response to a:
TRIGGER
The SRD describes it as a special action taken in response to something that happens.
WHAT IS A TRIGGER?
A trigger is the event that allows a particular Reaction to occur.
For example:
“When a creature leaves your reach…”
could be a trigger.
Or:
“When you are hit by an attack…”
could be the trigger for some feature.
Or:
“When a creature you can see casts a spell…”
could be the trigger for another rule.
The Reaction's description tells you what event activates the option.
NO TRIGGER, NO REACTION
A Reaction is not something you can normally take whenever you want.
You need:
A RULE THAT GIVES YOU A REACTION
and:
THE REQUIRED TRIGGER MUST OCCUR
Only then can you use that Reaction.
REACTIONS CAN HAPPEN ON SOMEONE ELSE'S TURN
This is one of their most important properties.
A Reaction can happen:
-
during your own turn
-
during another creature's turn
because the timing depends on its trigger.
EXAMPLE
It is an enemy's turn.
The enemy does something that triggers one of your Reactions.
You can use your Reaction even though:
IT IS NOT YOUR TURN
That is one of the major differences between a Reaction and a Bonus Action.
BONUS ACTION VS. REACTION
BONUS ACTION
Normally used:
on your own turn
and only if a rule gives you one.
REACTION
Used:
when its trigger occurs
which might happen during your turn or someone else's.
OPPORTUNITY ATTACKS
The SRD identifies the Opportunity Attack as the most common example of a Reaction.
An Opportunity Attack can occur when a creature you can see leaves your reach using certain forms of movement.
You then use your:
REACTION
to make one melee attack with a weapon or an Unarmed Strike before the creature actually leaves your reach.
We will examine Opportunity Attacks in greater detail later in the combat lessons.
ONE REACTION AT A TIME
After taking a Reaction:
YOU CANNOT TAKE ANOTHER REACTION UNTIL THE START OF YOUR NEXT TURN
This is one of the most important timing rules in the game.
EXAMPLE
An enemy triggers your Reaction.
You use it.
Later in the same round, another enemy triggers another possible Reaction.
You cannot use the second one yet.
You have already spent your Reaction.
You regain the ability to take another Reaction:
AT THE START OF YOUR NEXT TURN
REACTION RECOVERY IS NOT “ON YOUR TURN”
Pay attention to the exact timing.
It is not:
at the end of your turn
and not:
at the end of the round
It is:
AT THE START OF YOUR NEXT TURN
This distinction can matter.
EXAMPLE OF REACTION TIMING
Suppose your turn begins.
At that moment, your Reaction becomes available again.
You take your turn.
Later, during an enemy's turn, you use a Reaction.
You now cannot react again until:
THE START OF YOUR NEXT TURN
REACTIONS CAN OCCUR DURING YOUR OWN TURN
Because a Reaction is tied to a trigger rather than to another creature's turn, you can sometimes take a Reaction during your own turn.
The Rules Glossary confirms that if you take a Reaction on your turn, you can still also take:
-
an Action
-
a Bonus Action
-
or both
provided the rules otherwise allow them.
So a Reaction does not automatically replace your normal Action or Bonus Action.
ACTION + BONUS ACTION + REACTION
In a turn where all the appropriate rules allow it, a creature might potentially use:
one Action
one Bonus Action
and:
one Reaction
These are distinct resources.
However, remember:
the Reaction requires a valid trigger.
You don't simply receive one free extra action.
WHEN EXACTLY DOES A REACTION HAPPEN?
The SRD provides an important general timing rule:
A REACTION OCCURS IMMEDIATELY AFTER ITS TRIGGER
unless the Reaction's own description says otherwise.
EXAMPLE
Suppose a rule says:
“When a creature completes X, you can take this Reaction.”
The trigger happens.
Then:
THE REACTION OCCURS IMMEDIATELY AFTERWARD
unless that specific Reaction tells you to use different timing.
SOME REACTIONS INTERRUPT EVENTS
Certain Reaction rules can specify timing that occurs before something else is completed.
For example, an Opportunity Attack occurs:
RIGHT BEFORE THE CREATURE LEAVES YOUR REACH
because that specific rule tells us so.
Again:
SPECIFIC TIMING OVERRIDES GENERAL TIMING
WHAT IF A REACTION INTERRUPTS ANOTHER CREATURE'S TURN?
If you use a Reaction during another creature's turn:
-
that creature's turn is temporarily interrupted
-
resolve your Reaction
-
the creature continues its turn afterward
The SRD states this explicitly.
EXAMPLE
Enemy's turn:
1. Enemy begins moving.
2. Movement triggers your Reaction.
3. Resolve your Reaction.
4. Enemy resumes its turn.
The Reaction does not normally end the enemy's entire turn unless the Reaction's effect itself causes something that prevents further actions.
READY AND REACTIONS
In Lesson 10, you learned about the Ready action.
Ready provides one of the clearest examples of trigger-based timing.
When you Ready:
-
define a perceivable trigger
-
choose an action or movement to perform
-
wait
-
if the trigger occurs before your next turn, you can use your Reaction to perform the prepared response
EXAMPLE — READY
On your turn:
“I Ready an action. If the door opens, I attack the creature that comes through.”
You have now spent:
YOUR ACTION
to Ready.
Later, the door opens.
That is your:
TRIGGER
You may now spend:
YOUR REACTION
to perform the prepared attack.
YOU CAN IGNORE A READY TRIGGER
When a trigger occurs after you have Readied something:
you are not forced to respond.
You may:
use your Reaction
or:
ignore the trigger.
IF YOU HAVE ALREADY USED YOUR REACTION
Suppose you Ready something.
Before the trigger occurs, another event causes you to spend your Reaction.
Later, the Ready trigger happens.
You have no Reaction available.
Therefore:
YOU CANNOT PERFORM THE READIED RESPONSE
because Ready requires your Reaction.
READYING A SPELL
Ready has additional rules when the prepared action is a spell.
To Ready a spell:
-
the spell must have a casting time of an Action
-
you cast it normally when you Ready it
-
you expend the required resources at that time
-
you hold its magical energy
-
holding it requires Concentration
-
you release it using your Reaction when the trigger occurs
IF YOUR CONCENTRATION BREAKS
If you lose Concentration before releasing the readied spell:
THE SPELL DISSIPATES
and:
IT NEVER TAKES EFFECT
TRIGGERS MUST BE PERCEIVABLE FOR READY
The Ready action specifically requires you to choose a:
PERCEIVABLE CIRCUMSTANCE
as its trigger.
You cannot Ready based on something your character has no way of perceiving.
REACTION TIMING EXAMPLE
Suppose your Reaction says:
“When you see a creature enter a marked area…”
Enemy enters the area.
Trigger occurs.
Unless the Reaction's text provides another timing instruction:
RESOLVE THE REACTION IMMEDIATELY AFTER THE TRIGGER
Then the interrupted turn continues.
TIMING WORDS MATTER
When reading a feature, pay careful attention to words such as:
when
after
before
at the start of
at the end of
immediately after
These words determine when an effect can happen.
“WHEN” VS. “AFTER”
For example:
“When you are hit…”
and:
“After you take damage…”
are not necessarily the same timing.
The first may trigger at the moment the attack hits.
The second happens after damage has already occurred.
Always follow the exact wording of the specific rule.
“START OF YOUR TURN”
Many rules refresh or activate:
AT THE START OF YOUR TURN
A Reaction is one important example.
After using one, your ability to take another Reaction returns at:
THE START OF YOUR NEXT TURN
“UNTIL THE START OF YOUR NEXT TURN”
You saw this wording with Dodge.
If an effect lasts:
until the start of your next turn
it ends as your next turn begins.
This is different from:
until the end of your next turn.
Exact timing language matters.
ACTION ECONOMY
Players often use the informal phrase:
ACTION ECONOMY
to describe how a creature manages the different things it can do during a turn.
Within the rules we have studied, the important categories are:
MOVEMENT
Move according to your available Speed.
ACTION
Take one action at a time.
BONUS ACTION
Use one if a rule grants one.
REACTION
Use one when a valid trigger occurs, then wait until the start of your next turn to regain it.
These resources are separate, although specific rules can interact with them.
EXAMPLE — A COMPLETE TURN
Imagine your character has:
Speed 30 feet
a normal Action
and a feature that provides a Bonus Action.
Your turn might look like:
MOVEMENT
Move 15 feet.
ACTION
Attack.
MOVEMENT
Move the remaining 15 feet.
BONUS ACTION
Use your special feature.
Later, during an enemy's turn:
REACTION
Use a Reaction when its trigger occurs.
This illustrates how several different parts of the game's timing system can fit together.
ORDER CAN MATTER
Suppose your Bonus Action gives you a benefit to your next attack.
Then:
Bonus Action first → Attack second
may be useful.
If instead your Bonus Action can only be used after attacking:
Attack first → Bonus Action second
may be required.
The rules of each feature determine the legal timing.
YOU CANNOT CONVERT ACTION TYPES FREELY
Another common beginner mistake is assuming that:
an Action can always become a Bonus Action
or:
a Bonus Action can become an Action
or:
an unused Action gives you another Reaction
That is not a general rule.
Action types are separate.
You can only convert or substitute them if a specific rule explicitly allows it.
UNUSED BONUS ACTIONS DON'T ACCUMULATE
Suppose you have a Bonus Action available but choose not to use it.
You do not carry it into the next turn.
You cannot say:
“I skipped my Bonus Action last turn, so I have two now.”
Each turn is resolved according to the options available during that turn.
UNUSED REACTIONS DON'T ACCUMULATE
The same principle applies to Reactions.
If you never use your Reaction before your next turn:
you don't gain two.
You simply still have the ability to take one when the next valid trigger occurs.
INCAPACITATED AND TIMING
The Incapacitated condition is particularly important because it prevents:
-
Actions
-
Bonus Actions
-
Reactions
It also breaks Concentration.
This means a character who becomes Incapacitated can lose access to several parts of the action economy at once.
EXAMPLE — INCAPACITATED DURING A READIED SPELL
You Ready a spell.
Holding it requires Concentration.
Before the trigger happens, you become Incapacitated.
The Incapacitated condition breaks your Concentration.
Therefore:
the readied spell dissipates before it can be released.
COMMON BEGINNER MISTAKES
MISTAKE 1 — ASSUMING EVERY CHARACTER ALWAYS HAS A BONUS ACTION
A Bonus Action exists only when a rule gives you something to do as one.
MISTAKE 2 — USING MULTIPLE BONUS ACTIONS
You can take only:
ONE BONUS ACTION PER TURN
MISTAKE 3 — USING A REACTION WITHOUT A TRIGGER
A Reaction must be activated by the trigger specified by its rule.
MISTAKE 4 — THINKING REACTIONS ONLY HAPPEN ON ENEMY TURNS
A Reaction can occur on:
your turn
or:
someone else's turn
depending on the trigger.
MISTAKE 5 — USING MULTIPLE REACTIONS BEFORE YOUR NEXT TURN
Once you take one:
you cannot take another until:
THE START OF YOUR NEXT TURN
MISTAKE 6 — THINKING READY GIVES YOU AN EXTRA ACTION FOR FREE
Ready costs:
YOUR ACTION NOW
and the prepared response later costs:
YOUR REACTION
MISTAKE 7 — FORGETTING THAT READIED SPELLS REQUIRE CONCENTRATION
A readied spell must have a casting time of an Action, and holding it requires Concentration.
MISTAKE 8 — IGNORING EXACT TIMING WORDS
“Before,” “after,” “when,” “start,” and “end” can completely change how a rule works.
Read the trigger carefully.
LESSON 11 — KEY TAKEAWAYS
BONUS ACTIONS REQUIRE A RULE
You do not automatically have one.
A class feature, spell, or other rule must give you a Bonus Action option.
ONLY ONE BONUS ACTION PER TURN
If several are available:
choose one.
BONUS ACTION TIMING IS FLEXIBLE UNLESS SPECIFIED
You normally decide when during your turn to use it unless its rule gives specific timing.
REACTIONS RESPOND TO TRIGGERS
They can occur during your turn or another creature's turn.
AFTER USING A REACTION
You can't take another until:
THE START OF YOUR NEXT TURN
GENERAL REACTION TIMING
A Reaction normally happens:
IMMEDIATELY AFTER ITS TRIGGER
unless the specific Reaction says otherwise.
INTERRUPTED TURNS CONTINUE
After the Reaction resolves, the creature whose turn was interrupted normally continues its turn.
READY USES BOTH AN ACTION AND A REACTION
Take the Ready action now.
Respond to the trigger later using your Reaction.
NEXT LESSON
LESSON 12 — SOCIAL INTERACTION: ROLEPLAYING, ATTITUDES, INFLUENCE, AND SOCIAL CHECKS
You now understand how Actions, Bonus Actions, Reactions, and timing work.
Next we return to one of the three fundamental pillars of play:
SOCIAL INTERACTION
In Lesson 12, we will study:
-
how social encounters work
-
the GM's role in controlling NPCs
-
roleplaying
-
active and descriptive approaches to roleplaying
-
Friendly, Indifferent, and Hostile attitudes
-
how attitudes affect interactions
-
when a social Ability Check is necessary
-
when no check should be made
-
how Influence works within a full social encounter
-
Deception
-
Intimidation
-
Performance
-
Persuasion
-
Animal Handling
-
how roleplaying and game mechanics work together
SRD 5.2.1 ATTRIBUTION
This work includes material from the System Reference Document 5.2.1 (“SRD 5.2.1”) by Wizards of the Coast LLC, available at https://www.dndbeyond.com/srd. The SRD 5.2.1 is licensed under the Creative Commons Attribution 4.0 International License, available at https://creativecommons.org/licenses/by/4.0/legalcode.