D&D 5e Guide to Legendary Actions and Lairs

Legendary actions and lair actions for D&D 5e featured image is The Horde by NathanParkArt, CC License. This article contains affiliate links to put gold in our coffers.

For the Dungeon Master with players well-versed in Dungeons and Dragons, planning unexpected and intriguing combat with frequently-used monsters can be a challenge. Players who are themselves Dungeon Masters know the tactics, vulnerabilities, and strengths of your favorite rules-as-written monsters and can often figure out what they are fighting, even if you keep its identity unknown. With the challenge of homebrew monsters potentially being unbalanced or not fitting into your world setting, there are few options for a Dungeon Master to throw off their players. Even if a Dungeon Master doesn’t suffer from these problems, some encounters simply lack versatility and challenges beyond hacking-and-slashing monsters. 

I propose, in addition to using interactive battle elements and hazards, a dungeon master should consider giving nearly all battles lair effects, lair actions, and possibly legendary actions. 

In addition to this article’s content, you may enjoy the popular DMs Guild book “Home-Field Advantage – A Compendium of Lair Actions” to spice up lair actions.

Lair Actions and Regional Effects

Let’s explore all the angles that a DM should explore to effectively use lair actions and regional effects.

Here’s Why

Imagine your adventurers entering a goblin stronghold. Players can easily handle batches of 3-8 goblins at a time with no problems, even at low levels. However, defending in their own home, these goblins should have some sort of tactical advantage over the players, such as knowing where secret passages are for attack-and-run tactics, utilizing alchemist’s fire as defense techniques, and setting quick mechanical traps to keep invaders at bay. 

In fact, I would argue that any magical creature being fought on its own turf should have a tactical advantage in the form of lair effects or lair actions, as they would want to protect against predators. The area surrounding a Displacer Beast’s burrow could emit some sort of effect, like magical illusions that flicker or a stench that requires continual Constitution saving throws. Sprites, who are mischievous by nature, could set up traps and hazards around their nomadic “camps.” These lair effects and actions will not be game-breaking, but they will provide additional challenges for players to overcome, adding a layer of depth to any encounter.

The Mechanics

Basic Rules monsters with lairs include the aboleths, dragons, wyrmlings, and unicorns. From these monsters, we can get the gist of the mechanics of lair effects and actions. To set up a formidable lair, consider including the following:

1. Lair Terrain. Establish intriguing terrain for the lair to exist in, such as icy caves, subterranean chambers, labyrinthine jungles, cloudy mountain peaks, subterranean lakes, volcanic caves, marshy woods, idyllic ponds, mist-shrouded islands, ancient ruins, behind sparkling waterfalls, or in locations only accessible by unique travel like flying, deep-diving, or spelunking.   
2. Lair Actions. Ambient magic in a monster’s lair may cause unique and unexpected actions to take place. Typically, a lair has 2-4 actions that take place on initiative count 20 (losing initiative ties), and only one action is triggered per round. Actions may include spellcasting by the monster without requiring spell slots or components; environmental effects like tides of water overtaking creatures, swarming clouds of insects, grasping roots, collapsing ceilings, swirling and blinding sand, striking lightning, strong winds, and spreading fog; or magical effects like spreading darkness, banishing creatures to a dream plane, or self-healing.
3. Regional Effects. Often, the land surrounding a magical creature’s lair has become warped with the creature’s magic. This may only apply to large and powerful creatures who have lived in their lairs for years. These effects include things like a fog obscuring the land within a few miles of the lair, curses plaguing the land, non-magical fires being unable to light, weather can be controlled by the monster, illusory sounds and images may occur, and the monster may have telepathy with creatures within a few miles of its lair.

Toward the end of this article, we will list all known lair effects/actions and regional effects from the basic rules as well as our own that we have homebrewed. Let us now discuss the addition of Legendary Actions.

Lair Descriptions

An effective lair will have unique details that add to its atmosphere. This may include tactics the monsters use or storytelling lore. Here are some of our favorites from the basic rules:

Adult Black Dragon: “A black dragon’s lair is a dismal cave, grotto, or ruin that is at least partially flooded, providing pools where the dragon rests and where its victims can ferment. The lair is littered with the acid-pitted bones of previous victims and the fly-ridden carcasses of fresh kills, watched over by crumbling statues. Centipedes, scorpions, and snakes infest the lair, which is filled with the stench of death and decay.”

Adult Blue Dragon: “Blue dragons make their lairs in barren places, using their lightning breath and their burrowing ability to carve out crystallized caverns and tunnels beneath the sands. Thunderstorms rage around a legendary blue dragon’s lair, and narrow tubes lined with glassy sand ventilate the lair, all the while avoiding the deadly sinkholes that are the dragon’s first line of defense. A blue dragon will collapse the caverns that make up its lair if that lair is invaded. The dragon then burrows out, leaving its attackers to be crushed and suffocated. When it returns later, it collects its possessions — along with the wealth of the dead intruders.”

Adult Green Dragon: “A forest controlled by a green dragon is easy to spot. A perpetual fog hangs in the air in a legendary green dragon’s wood, carrying an acrid whiff of the creature’s poison breath. The moss-covered trees grow close together except where winding pathways trace their way like a maze into the heart of the forest. The light that reaches the forest floor carries an emerald green cast, and every sound seems muffled.”

Legendary Actions

The most legendary of monsters get a boost to their action economies in the form of Legendary Actions. Let’s explore how they can help DMs to nail their boss fights.

Here’s Why We Use Legendary Actions

Need to scale up an encounter? Add one or two legendary actions. Have a monster you need to distinguish from its allies? Legendary actions! Do you have a trigger to your encounter that would end it quickly? Give the monster that would end the fight a few legendary actions.

Not only do legendary actions subvert player expectations of monsters, but they also give your players another threat to focus on that may require clever strategies to overcome. Legendary actions can also seem a lot scarier than the actual mechanics allow for. Intimidate your players with unexpected attacks and actions. 

The Mechanics of Legendary Actions

From the same list of monsters that have lairs, let’s carve out what legendary actions may look like. Legendary actions are usually attacks or spellcasting abilities taken outside of a creature’s turn. Typically, a creature with legendary actions has 1-3 options that have different action costs and a set number of actions that can be used per round. Each option costs 1 action unless otherwise stated. Only one legendary action can be used at a time; legendary actions can only be taken at the end of another creature’s turn; a creature regains its legendary actions at the start of its turn. This is a lot to digest, so let’s illustrate it.

An Adult Black Dragon has three legendary options (Detect, Tail Attack, and Wing Attack) and three legendary actions per round of combat. Detect and Tail Attack both cost one action, while Wing Attack is more powerful and thus requires two of its three actions per round. 

After Player 1 attacks, the dragon could take one of its three options. If the dragon uses Detect or Tail Attack, it would have spent 1 action and would have 2 more actions to use after Player 2’s or subsequent players’ turns. If the dragon had used Wing Attack, it would have spent 2 actions. It would have had only 1 more action available before its next turn, so it could use Detect or Tail Attack after another player’s turn but not Wing Attack again because it doesn’t have enough actions.

When an Adult Black Dragon has expended all 3 of its actions, it cannot take another legendary action that round. The dragon would regain its 3 actions/round at the start of its turn. 

How Does Including Legendary Actions or Lair Effects Increase CR?

The best way for a Dungeon Master to gauge how adding a Lair Effect or Legendary Action will affect an encounter’s challenge rating is by using the Experience Point Value table from Wizards of the Coast and finding similar examples in existing monsters.

A Dungeon Master will take into account the number of actions a creature will have per round (including legendary actions and lair effects), the average amount of damage players could take per round, and how many debuffs players may receive, which will decrease their average damage output.

There is no quick mathematical way to calculate a new challenge rating, but perhaps we can compare a few creatures with and without legendary actions and lair effects and see what causes a change in CR:

First, let’s compare an Aboleth, a Deva, a Stone Golem, and a Young Gold Dragon, all of which are CR 10. The Aboleth and the Young Gold Dragon both have lairs, but only the Aboleth has legendary actions.

Typical Aboleth Turn: 

Note that an Aboleth has AC 17 and 135 hit points. They also receive a +9 to hit.

An Aboleth could take three tentacle attacks (12 damage per hit, plus a Constitution ST or a target becomes diseased, which comes into effect in 10 rounds/1 minute); an Aboleth could make a Tail attack (15 damage); or, three times per day, an Aboleth could attempt to charm a target (DC 14), taking them under control.

Each round, an Aboleth could also do Legendary Actions such as another Tail attack or a Psychic Drain (10 damage) on a charmed creature, which also allows the Aboleth to regain hit points.

Lair actions will also contribute by causing one of the following effects per round: forcing a target to focus on a Phantasmal Force illusion for their action, using water to pull in and knock prone targets, or attacking with water for 7 damage.

The range of damage from an Aboleth per round is 25 to 70, plus removing one charmed person from combat and stealing another’s action.

Typical Deva Turn:

Note that a Deva has AC 17 and 136 hit points. They receive a +8 to hit.

Devas may make two melee attacks for 25 total magical damage. They have non-combative spellcasting and advantage to saving throws against spells and magical effects. They may heal 20 hit points to any creature, and they may polymorph into any creature of its own CR or lower, but they will retain their hit points. Let’s assume they become a Tyrannosaurus Rex and have +10 to hit and do 26 damage per round.

The typical round of combat for a Deva will result in about 50 points of damage or healing itself 20 points.

Typical Stone Golem Turn:

Note that a Stone Golem has AC 17 and 178 hit points. They receive +10 to hit.

Stone Golems have straightforward turns. Their forms cannot be altered, they have advantage on saving throws against spells and other magical effects, and their weapons are magical.

A Stone Golem can make two slam attacks for 19 damage each, and it can debuff a player’s speed/reactions/action economy with a 1/3 chance of recharging. 

The typical round of combat for a Stone Golem will result in 38 damage or reducing a target’s abilities.

Typical Young Gold Dragon Turn:

Note that a Young Gold Dragon has AC 18 and 178 hit points. They have a +10 to hit.

A typical Young Gold Dragon turn includes three attacks for 43 damage, Fire Breath for 55 damage per target in a 30-foot cone (DC 17), or a debuff (DC 17) for disadvantage on Strength saving throws and ability checks. 

The range of damage for a Young Gold Dragon per round is 43 to potentially 55*21 medium-sized creatures in the 30-foot cone, assuming they all fail their saving throws. 

Lair effects of a Young Gold Dragon may also allow it advantage on saving throws and ability checks or to banish a target into a dream plane until the next round.

Creature	Actions Per Round	Hit Points	Damage/Round	Debuff Players	Incapacitate Players	Healing Abilities
Aboleth (Legendary Actions + Lair Effects)	5	135	25-70	—	Yes	—
Deva	2	136	50	—	—	20
Stone Golem	2	178	38	Yes	—	—
Young Gold Dragon (Lair Effects)	4	178	43-55*21	Yes	Yes	—

While each of these creatures provides 5,900 XP, there is a wide range of abilities, damage output, and additional effects per creature. I would rank this group of monsters from lowest difficulty to hardest: Deva, Stone Golem, Aboleth, and Young Gold Dragon. 

While adding legendary actions and lair effects to your own encounters, consider keeping in scale with this range of damage output, hit points, and abilities to debuff or incapacitate players. Look at creatures with the same CR and creatures with a CR one higher, count the number of actions per round, hit points, damage per round, and extra abilities, and decide if your monster with unexpected legendary actions and lair effects fits within those CR ranges.

For more reading on the topic, consider this RPG Stack Exchange answer.

Reference Tables

Below are all legendary actions, lair actions, and regional effects from the basic rules compiled into easy-to-reference tables. At the end of the Legendary Actions table, we have also listed our own ideas for legendary actions and their costs. It is our hope that these tables will guide you to developing your own balanced and unique abilities for your favorite monsters.

Table of Legendary Actions

Some of these effects have been edited to be general so that a Dungeon Master could use them for their purposes. Note that “creature” will refer to the one using the legendary action and “target” will refer to the target of the legendary action.

A legendary action will take 1 action unless otherwise specified.

Legendary Action	Effect	Monsters That Use It
Detect	The creature makes a Wisdom (Perception) check.	Aboleth (CR 10), Adult and Ancient Dragons (CR 14 and 20)
Tail Swipe	The creature makes one tail attack.	Aboleth (CR 10), Adult and Ancient Dragons (CR 14 and 20)
Claw Attack	The creature makes one claw attack.	Androsphinx (CR 17), Gynosphinx (CR 11)
Tentacle Attack or Fling	The creature makes one tentacle attack or uses its Fling: One Large or smaller object held or creature grappled by the creature is thrown up to 60 feet in a random direction and knocked prone. If a thrown target strikes a solid surface, the target takes 3 (1d6) bludgeoning damage for every 10 feet it was thrown. If the target is thrown at another creature, that creature must succeed on a DC 18 Dexterity saving throw or take the same damage and be knocked prone.	Kraken (CR 23)
Cantrip	The creature casts a cantrip.	Lich (CR 21)
Attack	The creature makes one attack or uses one of its other actions.	Mummy Lord (CR 15), Tarrasque (CR 30)
Blinding Dust	Blinding dust and sand swirls magically around the creature. Each target within 5 feet of the creature must succeed on a DC 16 Constitution saving throw or be blinded until the end of the target’s next turn.	Mummy Lord (CR 15)
Move	The creature moves up to half its speed (does not provoke opportunity attacks for a Vampire).	Tarrasque (CR 30), Vampire (CR 13)
Hooves	The creature makes one attack with its hooves.	Unicorn (CR 5)
Unarmed Strike	The creature makes one unarmed strike.	Vampire (CR 13)
Teleport (costs 1 or 2 actions depending on the creature)	The creature magically teleports, along with any equipment it is wearing or carrying, up to 120 feet to an unoccupied space it can see.	Androsphinx (CR 17), Gynosphinx (CR 11), Solar (CR 21)
Wing Attack (costs 2 actions)	The creature beats its wings. Each creature within 10 feet of the dragon must succeed on a DC 19 Dexterity saving throw or take 13 (2d6 + 6) bludgeoning damage and be knocked prone. The dragon can then fly up to half its flying speed.	Adult and Ancient Dragons (CR 14 and 20)
Lightning Storm (Costs 2 Actions)	The creature uses Lightning Storm: the creature magically creates three bolts of lightning, each of which can strike a target the creature can see within 120 feet of it. A target must make a DC 23 Dexterity saving throw, taking 22 (4d10) lightning damage on a failed save, or half as much damage on a successful one.	Kraken (CR 23)
Paralyzing Touch (Costs 2 Actions)	The creature uses its Paralyzing Touch: Melee Spell Attack: +12 to hit, reach 5 ft., one creature. Hit: 10 (3d6) cold damage. The target must succeed on a DC 18 Constitution saving throw or be paralyzed for 1 minute. The target can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success.	Lich (CR 21)
Frightening Gaze (Costs 2 Actions)	The creature fixes its gaze on one creature it can see within 10 feet of it. The target must succeed on a DC 18 Wisdom saving throw against this magic or become frightened for 1 minute. The frightened target can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success. If a target’s saving throw is successful or the effect ends for it, the target is immune to the creature’s gaze for the next 24 hours.	Lich (CR 21)
Blasphemous Word (Costs 2 Actions)	The creature utters a blasphemous word. Each non-undead target within 10 feet of the creature that can hear the magical utterance must succeed on a DC 16 Constitution saving throw or be stunned until the end of the creature’s next turn.	Mummy Lord (CR 15)
Whirlwind of Sand (Costs 2 Actions)	The creature magically transforms into a whirlwind of sand, moves up to 60 feet, and reverts to its normal form. While in whirlwind form, the creature is immune to all damage, and it can’t be grappled, petrified, knocked prone, restrained, or stunned. Equipment worn or carried by the creature remains in its possession.	Mummy Lord (CR 15)
Searing Burst (Costs 2 Actions)	The creature emits magical, divine energy. Each target of its choice in a 10-foot radius must make a DC 23 Dexterity saving throw, taking 14 (4d6) fire damage plus 14 (4d6) radiant damage on a failed save, or half as much damage on a successful one.	Solar (CR 21)
Chomp (Costs 2 Actions)	The creature makes one bite attack or uses its Swallow: The creature makes one bite attack against a Large or smaller target it is grappling. If the attack hits, the target takes the bite’s damage, the target is swallowed, and the grapple ends. While swallowed, the target is blinded and restrained, it has total cover against attacks and other effects outside the creature, and it takes 56 (16d6) acid damage at the start of each of the creature’s turns. If the creature takes 60 damage or more on a single turn from a target inside it, the creature must succeed on a DC 20 Constitution saving throw at the end of that turn or regurgitate all swallowed targets, which fall prone in a space within 10 feet of the creature. If the creature dies, a swallowed target is no longer restrained by it and can escape from the corpse by using 30 feet of movement, exiting prone.	Tarrasque (CR 30)
Shimmering Shield (Costs 2 Actions)	The creature creates a shimmering, magical field around itself or another target it can see within 60 feet of it. The target gains a +2 bonus to AC until the end of the creature’s next turn.	Unicorn (CR 5)
Bite (Costs 2 Actions)	The creature makes one bite attack.	Vampire (CR 13)
Cast a Spell (Costs 3 Actions)	The creature casts a spell from its list of prepared spells, using a spell slot as normal.	Androsphinx (CR 17), Gynosphinx (CR 11)
Ink Cloud (Costs 3 Actions)	While underwater, the creature expels an ink cloud in a 60-foot radius. The cloud spreads around corners, and that area is heavily obscured to creatures other than the creature. Each creature other than the creature that ends its turn there must succeed on a DC 23 Constitution saving throw, taking 16 (3d10) poison damage on a failed save, or half as much damage on a successful one. A strong current disperses the cloud, which otherwise disappears at the end of the creature’s next turn.	Kraken (CR 23)
Disrupt Life (Costs 3 Actions)	Each non-undead target within 20 feet of the creature must make a DC 18 Constitution saving throw against this magic, taking 21 (6d6) necrotic damage on a failed save, or half as much damage on a successful one.`	Lich (CR 21)
Blinding Gaze (Costs 3 Actions)	The creature targets one target it can see within 30 feet of it. If the target can see it, the target must succeed on a DC 15 Constitution saving throw or be blinded until magic such as the lesser restoration spell removes the blindness.	Solar (CR 21)
Heal Self (Costs 3 Actions)	The creature magically regains 11 (2d8 + 2) hit points.	Unicorn (CR 5)

17 Ideas for Legendary Actions

1. A creature uses any one of its abilities.
2. A creature can cast one of its level 1 spells.
3. The creature targets one creature it can see. The target must make an Intelligence saving throw DC 16 or take 10 (3d6) psychic damage. The creature regains hit points equal to the damage taken.
4. A creature emboldens each of its allies within 60 feet of it. All emboldened allies cannot be frightened, charmed, or put to sleep, and gain advantage on all ability checks and saving throws until the end of the creature’s next turn.
5. A creature causes a swarm of insects to appear within 30 feet of it.
6. The creature rolls a d8 and gains one immediate use of one of the following spells: (1) Acid Splash, (2) Chill Touch, (3) Eldritch Blast, (4) Fire Bolt, (5) Infestation, (6) Lightning Lure, (7) Mage Hand, (8) Mold Earth.
7. (Costs 2 Actions). The creature targets one target it can see within 30 feet of it. The next time the creature takes damage, the target must make a Con ST DC 18 or take half the damage in place of the creature.
8. (Costs 2 Actions) A creature casts one of its spells at-will.
9. (Costs 2 Actions). A creature and its mount will both make one attack each.
10. (Costs 2 Actions) A creature releases a line of wind spanning 50 feet long and 15 feet wide. Each target in the path of the wind must make a Strength saving throw DC 15. On a failed save, a target takes 22 (4d10) bludgeoning damage or half as much damage on a successful save. Projectiles launched at the wind line are deflected upward and automatically miss. Gases cannot pass through it.
11. (Costs 2 Actions) A creature summons one beast of CR 2 or lower, two beasts of CR 1 or lower, four beasts of CR 1/2 or lower, or eight beasts of CR 1/4 or lower. This beast is friendly to the creature and follows verbal commands issued by the creature. The beasts will defend on their turn if they are not commanded to take any other action.
12. (Costs 2 Actions) A creature moves up to its speed and makes one attack.
13. (Costs 3 Actions) A creature targets one target within 60 feet. That target must make a Wisdom saving throw DC 16 or lose a spell slot of level 3 or lower. The creature gains a spell slot of the level that was lost.
14. (Costs 3 Actions) A creature targets one target it can see within 60 feet. That target must make a DC 15 Wisdom saving throw. On a failed save, the target is cursed. While cursed, the target has disadvantage on attack rolls against the creature, has disadvantage on all ability checks, and if attacked by the creature, the target will take an additional 1d8 necrotic damage. At the end of each of the target’s turns, the target can reroll its Wisdom saving throw.
15. (Costs 3 Actions). A creature weaves a web around itself. Each target within 10 feet must make a Strength saving throw DC 16 or be restrained until the end of the creature’s next turn.
16. (Costs 3 Actions). A creature points its finger at a corpse and fills it with necrotic energy until it explodes. Each target within 10 feet of the corpse must make a Dexterity saving throw DC 16. A target takes 27 (5d10) necrotic damage on a failed save, and half as much damage on a successful one.
17. (Costs 3 Actions) A creature magically releases a psychic screech in a 60-foot cone. Each target in the area must succeed on a DC 16 Intelligence saving throw or receive one level of exhaustion.

Table of Lair Actions and Regional Effects

Some of these actions and effects have been edited to be general so that a Dungeon Master could use them for their purposes. Note that “creature” will refer to the one who controls the lair, and “target” will refer to the target of the lair actions and regional effects.

On initiative count 20 (losing initiative ties), the creature takes a lair action to cause one of the following effects; the creature can’t use the same effect two rounds in a row.

Lair Action	Terrain	Monsters That Use It
The creature casts phantasmal force (no components required) on any number of targets it can see within 60 feet of it. While maintaining concentration on this effect, the creature can’t take other lair actions. If a target succeeds on the saving throw or if the effect ends for it, the target is immune to the creature’s phantasmal force lair action for the next 24 hours, although such a target can choose to be affected.	Subterranean lakes, rocky depths of ocean, ancient fallen underwater city	Aboleth (CR 10)
Pools of water within 90 feet of the creature surge outward in a grasping tide. Any creature on the ground within 20 feet of such a pool must succeed on a DC 14 Strength saving throw or be pulled up to 20 feet into the water and knocked prone. The creature can’t use this lair action again until it has used a different one.	Subterranean lakes, rocky depths of ocean, ancient fallen underwater city, swamp on frayed edge of civilization, in a dismal cave, grotto, ruin that is partially flooded	Aboleth (CR 10), Black Dragon (CR 2, 7 14, 21)
Water in the creature’s lair magically becomes a conduit for the creature’s rage. The creature can target any number of targets it can see in such water within 90 feet of it. A target must succeed on a DC 14 Wisdom saving throw or take 7 (2d6) psychic damage. The creature can’t use this lair action again until it has used a different one.	Subterranean lakes, rocky depths of ocean, ancient fallen underwater city.	Aboleth (CR 10)
A cloud of swarming insects fills a 20-foot-radius sphere centered on a point the creature chooses within 120 feet of it. The cloud spreads around corners and remains until the creature dismisses it as an action, uses this lair action again, or dies. The cloud is lightly obscured. Any target in the cloud when it appears must make a DC 15 Constitution saving throw, taking 10 (3d6) piercing damage on a failed save, or half as much damage on a successful one. A target that ends its turn in the cloud takes 10 (3d6) piercing damage.	Swamp on frayed edge of civilization, in a dismal cave, grotto, ruin that is partially flooded.	Black Dragon (CR 2, 7, 14, 21)
Magical darkness spreads from a point the creature chooses within 60 feet of it, filling a 15-foot-radius sphere until the creature dismisses it as an action, uses this lair action again, or dies. The darkness spreads around corners. A target with darkvision can’t see through this darkness, and nonmagical light can’t illuminate it. If any of the effect’s area overlaps with an area of light created by a spell of 2nd level or lower, the spell that created the light is dispelled.	Swamp on frayed edge of civilization, in a dismal cave, grotto, ruin that is partially flooded.	Black Dragon (CR 2, 7, 14, 21)
Part of the ceiling collapses above one target that the creature can see within 120 feet of it. The target must succeed on a DC 15 Dexterity saving throw or take 10 (3d6) bludgeoning damage and be knocked prone and buried. The buried target is restrained and unable to breathe or stand up. A target can take an action to make a DC 10 Strength check, ending the buried state on a success.	Barren lands with crystallized caverns and tunnels beneath the sands.	Blue Dragon (CR 3, 9, 16, 23)
A cloud of sand swirls about in a 20-foot-radius sphere centered on a point the creature can see within 120 feet of it. The cloud spreads around corners. Each target in the cloud must succeed on a DC 15 Constitution saving throw or be blinded for 1 minute. A target can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success.	Barren lands with crystallized caverns and tunnels beneath the sands. Ruin, canyon, cave network with ceiling holes for sunlight.	Blue Dragon (CR 3, 9, 16, 23), Brass Dragon (CR 1, 6, 13, 20)
Lightning arcs, forming a 5-foot-wide line between two of the lair’s solid surfaces that the creature can see. They must be within 120 feet of the creature and 120 feet of each other. Each target in that line must succeed on a DC 15 Dexterity saving throw or take 10 (3d6) lightning damage.	Barren lands with crystallized caverns and tunnels beneath the sands.	Blue Dragon (CR 3, 9, 16, 23)
A strong wind blows around the creature. Each target within 60 feet of the creature must succeed on a DC 15 Strength saving throw or be pushed 15 feet away from the creature and knocked prone. Gases and vapors are dispersed by the wind, and unprotected flames are extinguished. Protected flames, such as lanterns, have a 50 percent chance of being extinguished.	Ruin, canyon, cave network with ceiling holes for sunlight.	Brass Dragon (CR 1, 6, 13, 20)
The creature creates fog as though it had cast the fog cloud spell. The fog lasts until initiative count 20 on the next round.	Coastal cave, salvaged shipwreck. Secluded cold mountain within the clouds, natural cavern complexes or abandoned mines, abandoned mountain citadel or remote abandoned wizard tower.	Bronze Dragon (CR 2, 8, 15, 20), Silver Dragon (CR 2, 9, 15, 23)
A thunderclap originates at a point the creature can see within 120 feet of it. Each target within a 20-foot radius centered on that point must make a DC 15 Constitution saving throw or take 5 (1d10) thunder damage and be deafened until the end of its next turn.	Coastal cave, salvaged shipwreck.	Bronze Dragon (CR 2, 8, 15, 20)
The creature chooses a point on the ground that it can see within 120 feet of it. Stone spikes sprout from the ground in a 20-foot radius centered on that point. The effect is otherwise identical to the spike growth spell and lasts until the dragon uses this lair action again or until the creature dies.	Dry uplands or hilltop, in narrow caves.	Copper Dragon (CR 1, 7, 14, 21)
The creature chooses a 10-foot-square area on the ground that it can see within 120 feet of it. The ground in that area turns into 3-foot-deep mud. Each target on the ground in that area when the mud appears must succeed on a DC 15 Dexterity saving throw or sink into the mud and become restrained. A target can take an action to attempt a DC 15 Strength check, freeing itself or another creature within its reach and ending the restrained condition on a success. Moving 1 foot in the mud costs 2 feet of movement. On initiative count 20 on the next round, the mud hardens, and the Strength DC to work free increases to 20.	Dry uplands or hilltop, in narrow caves.	Copper Dragon (CR 1, 7, 14, 21)
The creature glimpses the future, so it has advantage on attack rolls, ability checks, and saving throws until initiative count 20 on the next round.	Idyllic lakes, mist-shrouded islands, cave complexes behind waterfalls, ancient ruins out of the way	Gold Dragon (CR 3, 10, 17, 24)
One target the creature can see within 120 feet of it must succeed on a DC 15 Charisma saving throw or be banished to a dream plane, a different plane of existence the creature has imagined into being. To escape, the target must use its action to make a Charisma check contested by the creature’s. If the target wins, it escapes the dream plane. Otherwise, the effect ends on initiative count 20 on the next round. When the effect ends, the target reappears in the space it left or in the nearest unoccupied space if that one is occupied.	Idyllic lakes, mist-shrouded islands, cave complexes behind waterfalls, ancient ruins out of the way	Gold Dragon (CR 3, 10, 17, 24)
Grasping roots and vines erupt in a 20-foot radius centered on a point on the ground that the creature can see within 120 feet of it. That area becomes difficult terrain, and each target there must succeed on a DC 15 Strength saving throw or be restrained by the roots and vines. A target can be freed if it or another target takes an action to make a DC 15 Strength check and succeeds. The roots and vines wilt away when the creature uses this lair action again or when the creature dies.	Marshy woods, subarctic taia, cliff or hillside with a hidden entrance, cave mouths behind waterfalls, partially submerged caverns, entrance behind vegetation.	Green Dragon (CR 2, 8, 15, 22)
A wall of tangled brush bristling with thorns springs into existence on a solid surface within 120 feet of the creature. The wall is up to 60 feet long, 10 feet high, and 5 feet thick, and it blocks line of sight. When the wall appears, each target in its area must make a DC 15 Dexterity saving throw. A target that fails the save takes 18 (4d8) piercing damage and is pushed 5 feet out of the wall’s space, appearing on whichever side of the wall it wants. A target can move through the wall, albeit slowly and painfully. For every 1 foot a target travels through the wall, it must spend 4 feet of movement. Furthermore, a target in the wall’s space must make a DC 15 Dexterity saving throw once each round it’s in contact with the wall, taking 18 (4d8) piercing damage on a failed save, or half as much damage on a successful one. Each 10-foot section of wall has AC 5, 15 hit points, vulnerability to fire damage, resistance to bludgeoning and piercing damage, and immunity to psychic damage. The wall sinks back into the ground when the creature uses this lair action again or when the creature dies.	Marshy woods, subarctic taia, cliff or hillside with a hidden entrance, cave mouths behind waterfalls, partially submerged caverns, entrance behind vegetation.	Green Dragon (CR 2, 8, 15, 22)
Magical fog billows around one target the creature can see within 120 feet of it. The target must succeed on a DC 15 Wisdom saving throw or be charmed by the creature until initiative count 20 on the next round.	Marshy woods, subarctic taia, cliff or hillside with a hidden entrance, cave mouths behind waterfalls, partially submerged caverns, entrance behind vegetation.	Green Dragon (CR 2, 8, 15, 22)
Magma erupts from a point on the ground the creature can see within 120 feet of it, creating a 20-foot-high, 5-foot-radius geyser. Each target in the geyser’s area must make a DC 15 Dexterity saving throw, taking 21 (6d6) fire damage on a failed save, or half as much damage on a successful one.	High mountains or hills in caverns under snow-capped peaks, deep within abandoned mines and dwarven strongholds, caves with volcanic activity.	Red Dragon (CR 4, 10, 17, 24)
A tremor shakes the lair in a 60-foot radius around the creature. Each target other than the creature on the ground in that area must succeed on a DC 15 Dexterity saving throw or be knocked prone.	High mountains or hills in caverns under snow-capped peaks, deep within abandoned mines and dwarven strongholds, caves with volcanic activity.	Red Dragon (CR 4, 10, 17, 24)
Volcanic gases form a cloud in a 20-foot-radius sphere centered on a point the creature can see within 120 feet of it. The sphere spreads around corners, and its area is lightly obscured. It lasts until initiative count 20 on the next round. Each target that starts its turn in the cloud must succeed on a DC 13 Constitution saving throw or be poisoned until the end of its turn. While poisoned in this way, a target is incapacitated.	High mountains or hills in caverns under snow-capped peaks, deep within abandoned mines and dwarven strongholds, caves with volcanic activity.	Red Dragon (CR 4, 10, 17, 24)
A blisteringly cold wind blows through the lair near the creature. Each target within 120 feet of the creature must succeed on a DC 15 Constitution saving throw or take 5 (1d10) cold damage. Gases and vapors are dispersed by the wind, and unprotected flames are extinguished. Protected flames, such as lanterns, have a 50 percent chance of being extinguished.	Secluded cold mountain within the clouds, natural cavern complexes or abandoned mines, abandoned mountain citadel or remote abandoned wizard tower.	Silver Dragon (CR 2, 9, 16, 23)
Freezing fog fills a 20-foot-radius sphere centered on a point the creature can see within 120 feet of it. The fog spreads around corners, and its area is heavily obscured. Each target in the fog when it appears must make a DC 10 Constitution saving throw, taking 10 (3d6) cold damage on a failed save, or half as much damage on a successful one. A target that ends its turn in the fog takes 10 (3d6) cold damage. A wind of at least 20 miles per hour disperses the fog. The fog otherwise lasts until the creature uses this lair action again or until the creature dies.	Icy caves, deep subterranean chambers far from the sun, high mountain vales accessible only by flying, caverns in cliff faces, labyrinthe ice caves in glaciers.	White Dragon (CR 2, 6, 13, 20)
Jagged ice shards fall from the ceiling, striking up to three creatures underneath that the creature can see within 120 feet of it. The creature makes one ranged attack roll (+7 to hit) against each target. On a hit, the target takes 10 (3d6) piercing damage.	Icy caves, deep subterranean chambers far from the sun, high mountain vales accessible only by flying, caverns in cliff faces, labyrinthe ice caves in glaciers.	White Dragon (CR 2, 6, 13, 20)
The creature creates an opaque wall of ice on a solid surface it can see within 120 feet of it. The wall can be up to 30 feet long, 30 feet high, and 1 foot thick. When the wall appears, each target within its area is pushed 5 feet out of the wall’s space, appearing on whichever side of the wall it wants. Each 10-foot section of the wall has AC 5, 30 hit points, vulnerability to fire damage, and immunity to acid, cold, necrotic, poison, and psychic damage. The wall disappears when the creature uses this lair action again or when the creature dies.	Icy caves, deep subterranean chambers far from the sun, high mountain vales accessible only by flying, caverns in cliff faces, labyrinthe ice caves in glaciers.	White Dragon (CR 2, 6, 13, 20)

Regional Effect	Terrain	Monsters That Use It
Underground surfaces within 1 mile of the lair are slimy and wet and are difficult terrain.	Subterranean lakes, rocky depths of ocean, ancient fallen underwater city.	Aboleth (CR 10)
Water sources within 1 mile of the lair are supernaturally fouled. Enemies of the creature that drink such water vomit it within minutes.	Subterranean lakes, rocky depths of ocean, ancient fallen underwater city. Swamp on frayed edge of civilization, in a dismal cave, grotto, ruin that is partially flooded.	Aboleth (CR 10), Black Dragon (CR 2, 7, 14, 21)
As an action, the creature can create an illusory image of itself within 1 mile of the lair. The copy can appear at any location the creature has seen before or in any location a target charmed by the creature can currently see. Once created, the image lasts for as long as the creature maintains concentration, as if concentrating on a spell. Although the image is intangible, it looks, sounds, and can move like the creature. The creature can sense, speak, and use telepathy from the image’s position as if present at that position. If the image takes any damage, it disappears.	Subterranean lakes, rocky depths of ocean, ancient fallen underwater city.	Aboleth (CR 10)
The land within 6 miles of the lair takes twice as long as normal to traverse, since the plants grow thick and twisted, and the swamps are thick with reeking mud.	Swamp on frayed edge of civilization, in a dismal cave, grotto, ruin that is partially flooded.	Black Dragon (CR 2, 7, 14, 21)
Fog lightly obscures the land within 6 miles of the lair.	Swamp on frayed edge of civilization, in a dismal cave, grotto, ruin that is partially flooded.	Black Dragon (CR 2, 7, 14, 21)
Thunderstorms rage within 6 miles of the lair.	Barren lands with crystallized caverns and tunnels beneath the sands.	Blue Dragon (CR 3, 9, 16, 23)
Dust devils scour the land within 6 miles of the lair. A dust devil has the statistics of an air elemental, but it can’t fly, has a speed of 50 feet, and has an Intelligence and Charisma of 1 (−5).	Barren lands with crystallized caverns and tunnels beneath the sands.	Blue Dragon (CR 3, 9, 16, 23)
Hidden sinkholes form in and around the lair. A sinkhole can be spotted from a safe distance with a successful DC 20 Wisdom (Perception) check. Otherwise, the first target to step on the thin crust covering the sinkhole must succeed on a DC 15 Dexterity saving throw or fall 1d6 × 10 feet into the sinkhole.	Barren lands with crystallized caverns and tunnels beneath the sands.	Blue Dragon (CR 3, 9, 16, 23)
Tracks appear in the sand within 6 miles of the lair. The tracks lead to safe shelters and hidden water sources, while also leading away from areas that the creature prefers to remain undisturbed.	Ruin, canyon, cave network with ceiling holes for sunlight.	Brass Dragon (CR 1, 6, 13, 20)
Images of Large or smaller monsters haunt the desert sands within 1 mile of the lair. These illusions move and appear real, although they can do no harm. A target that examines an image from a distance can tell it’s an illusion with a successful DC 20 Intelligence (Investigation) check. Any physical interaction with an image reveals it to be an illusion, because objects pass through it.	Ruin, canyon, cave network with ceiling holes for sunlight.	Brass Dragon (CR 1, 6, 13, 20)
Whenever a target with an Intelligence of 3 or higher comes within 30 feet of a water source within 1 mile of the lair, the creature becomes aware of the target’s presence and location.	Ruin, canyon, cave network with ceiling holes for sunlight.	Brass Dragon (CR 1, 6, 13, 20)
Once per day, the creature can alter the weather in a 6-mile radius centered on its lair. The creature doesn’t need to be outdoors; otherwise the effect is identical to the control weather spell.	Coastal cave, salvaged shipwreck. Secluded cold mountain within the clouds, natural cavern complexes or abandoned mines, abandoned mountain citadel or remote abandoned wizard tower.	Bronze Dragon (CR 2, 8, 15, 20), Silver Dragon (CR 2, 9, 16, 23)
Underwater plants within 6 miles of the lair take on dazzlingly brilliant hues.	Coastal cave, salvaged shipwreck.	Bronze Dragon (CR 2, 8, 15, 20)
Within its lair, the creature can set illusory sounds, such as soft music and strange echoes, so that they can be heard in various parts of the lair.	Coastal cave, salvaged shipwreck.	Bronze Dragon (CR 2, 8, 15, 20)
Magic carvings of the creature’s smiling visage can be seen worked into stone terrain and objects within 6 miles of the lair.	Dry uplands or hilltop, in narrow caves.	Bronze Dragon (CR 2, 8, 15, 20)
Tiny beasts such as rodents and birds that are normally unable to speak gain the magical ability to speak and understand Draconic while within 1 mile of the lair. These creatures speak well of the creature, but can’t divulge its whereabouts.	Dry uplands or hilltop, in narrow caves.	Bronze Dragon (CR 2, 8, 15, 20)
Intelligent creatures within 1 mile of the lair are prone to fits of giggling. Even serious matters suddenly seem amusing.	Dry uplands or hilltop, in narrow caves.	Bronze Dragon (CR 2, 8, 15, 20)
Whenever a target that can understand a language sleeps or enters a state of trance or reverie within 6 miles of the lair, the creature can establish telepathic contact with that target and converse with it in its dreams. The target remembers its conversation with the creature upon waking.	Idyllic lakes, mist-shrouded islands, cave complexes behind waterfalls, ancient ruins out of the way.	Gold Dragon (CR 3, 10, 17, 24)
Banks of beautiful, opalescent mist manifest within 6 miles of the lair. The mist doesn’t obscure anything. It assumes haunting forms when evil creatures are near the creature or other non-evil targets in the mist, warning such targets of the danger.	Idyllic lakes, mist-shrouded islands, cave complexes behind waterfalls, ancient ruins out of the way.	Gold Dragon (CR 3, 10, 17, 24)
Gems and pearls within 1 mile of the lair sparkle and gleam, shedding dim light in a 5-foot radius.	Idyllic lakes, mist-shrouded islands, cave complexes behind waterfalls, ancient ruins out of the way.	Gold Dragon (CR 3, 10, 17, 24)
Thickets form labyrinthine passages within 1 mile of the lair. The thickets act as 10-foot-high, 10-foot-thick walls that block line of sight. Targets can move through the thickets, with every 1 foot a target moves costing it 4 feet of movement. A target in the thickets must make a DC 15 Dexterity saving throw once each round it’s in contact with the thickets or take 3 (1d6) piercing damage from thorns. Each 10-foot-cube of thickets has AC 5, 30 hit points, resistance to bludgeoning and piercing damage, vulnerability to fire damage, and immunity to psychic and thunder damage.	Marshy woods, subarctic taia, cliff or hillside with a hidden entrance, cave mouths behind waterfalls, partially submerged caverns, entrance behind vegetation.	Green Dragon (CR 2, 8, 15, 22)
Within 1 mile of its lair, the creature leaves no physical evidence of its passage unless it wishes to. Tracking it there is impossible except by magical means. In addition, it ignores movement impediments and damage from plants in this area that are neither magical nor creatures, including the thickets described above. The plants remove themselves from the creature’s path.	Marshy woods, subarctic taia, cliff or hillside with a hidden entrance, cave mouths behind waterfalls, partially submerged caverns, entrance behind vegetation.	Green Dragon (CR 2, 8, 15, 22)
Rodents and birds within 1 mile of the lair serve as the creature’s eyes and ears. Deer and other large game are strangely absent, hinting at the presence of an unnaturally hungry predator.	Marshy woods, subarctic taia, cliff or hillside with a hidden entrance, cave mouths behind waterfalls, partially submerged caverns, entrance behind vegetation.	Green Dragon (CR 2, 8, 15, 22)
Small earthquakes are common within 6 miles of the lair.	High mountains or hills in caverns under snow-capped peaks, deep within abandoned mines and dwarven strongholds, caves with volcanic activity.	Red Dragon (CR 4, 10, 17, 24)
Water sources within 1 mile of the lair are supernaturally warm and tainted by sulfur.	High mountains or hills in caverns under snow-capped peaks, deep within abandoned mines and dwarven strongholds, caves with volcanic activity.	Red Dragon (CR 4, 10, 17, 24)
Rocky fissures within 1 mile of the dragon’s lair form portals to the Elemental Plane of Fire, allowing creatures of elemental fire into the world to dwell nearby.	High mountains or hills in caverns under snow-capped peaks, deep within abandoned mines and dwarven strongholds, caves with volcanic activity.	Red Dragon (CR 4, 10, 17, 24)
Within 1 mile of the lair, winds buoy non-evil targets that fall due to no act of the creature’s or its allies. Such targets descend at a rate of 60 feet per round and take no falling damage.	Secluded cold mountain within the clouds, natural cavern complexes or abandoned mines, abandoned mountain citadel or remote abandoned wizard tower.	Silver Dragon (CR 2, 9, 16, 23)
Given days or longer to work, the creature can make clouds and fog within its lair as solid as stone, forming structures and other objects as it wishes.	Secluded cold mountain within the clouds, natural cavern complexes or abandoned mines, abandoned mountain citadel or remote abandoned wizard tower.	Silver Dragon (CR 2, 9, 16, 23)
Chilly fog lightly obscures the land within 6 miles of the lair.	Icy caves, deep subterranean chambers far from the sun, high mountain vales accessible only by flying, caverns in cliff faces, labyrinthe ice caves in glaciers.	White Dragon (CR 2, 6, 13, 20)
Freezing precipitation falls within 6 miles of the lair, sometimes forming blizzard conditions when the creature is at rest.	Icy caves, deep subterranean chambers far from the sun, high mountain vales accessible only by flying, caverns in cliff faces, labyrinthe ice caves in glaciers.	White Dragon (CR 2, 6, 13, 20)
Icy walls block off areas in the lair. Each wall is 6 inches thick, and a 10-foot section has AC 5, 15 hit points, vulnerability to fire damage, and immunity to acid, cold, necrotic, poison, and psychic damage. If the creature wishes to move through a wall, it can do so without slowing down. The portion of the wall the creature moves through is destroyed, however.	Icy caves, deep subterranean chambers far from the sun, high mountain vales accessible only by flying, caverns in cliff faces, labyrinthe ice caves in glaciers.	White Dragon (CR 2, 6, 13, 20)
Open flames of a nonmagical nature are extinguished within the creature’s domain. Torches and campfires refuse to burn, but closed lanterns are unaffected.	Ancient overgrown ruin, misty clearing in oaky forest, flowery hilltop with flora and fauna, serene woodlands.	Unicorn (CR 5)
Creatures native to the creature’s domain have an easier time hiding; they have advantage on all Dexterity (Stealth) checks made to hide.	Ancient overgrown ruin, misty clearing in oaky forest, flowery hilltop with flora and fauna, serene woodlands.	Unicorn (CR 5)
When a good-aligned target casts a spell or uses a magical effect that causes another good-aligned target to regain hit points, the target regains the maximum number of hit points possible for the spell or effect.	Ancient overgrown ruin, misty clearing in oaky forest, flowery hilltop with flora and fauna, serene woodlands.	Unicorn (CR 5)
Curses affecting any good-aligned creature are suppressed.	Ancient overgrown ruin, misty clearing in oaky forest, flowery hilltop with flora and fauna, serene woodlands.	Unicorn (CR 5)

If you enjoyed this article and are interested in more inspiration and a book of lair actions, check out the popular DMs Guild book “Home-Field Advantage – A Compendium of Lair Actions” to enhance your game. The Cleric Corner has reviewed that content and spoken about lair actions, too.