Create an unforgettable legendary battle with Lair action! Learn how to create dynamic and strategic D&D encounters with unique Lair effects.
What is lair action?
A proverb action occurs during combat when creatures of important power, such as dragons, sphinxes, and riches fight within the domain.
Unlike legendary behaviour, hideaways occur in initiative count 20 (relationships of lost initiatives) and provide thematic abilities to enhance the creature's influence on its surroundings. Whether it's an adult black dragon summoning a cloud of foul insects, or an abolition that evokes illusions to ruin the hearts of invaders, these effects are powerful and tides in court by the owner of the hideout. You can swing it.
When used, it usually continues with the effect caused by the hidden action until the creature ends the next turn or uses its hidden action again until the creature dies.
Rare actions in the new core rulebook
Lair's action has been removed from the new core rulebook in favor of providing additional legendary action and legendary resistance to legendary creatures.
This involves changes in legendary action, making them more common and dynamic, allowing legendary creatures to use more special abilities through combat.
That may be true, but we love the retreats we have here at Arcane Eye, so let's dive into this beloved system!
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How Lair Actions affect combat

The main feature of Lair Actions is to improve the action economy of legendary creatures and prevent boss monsters from being overwhelmed.
These effects give a different action to a legendary creature essentially, imposing debuffs, controlling the battlefield to enemy detriment, or dealing more damage depending on the creature type You can do it.
For example, an adult or an ancient red dragon can use the next hideout action while in the hideout.
Magma erupts from a point on the ground where the dragon can be seen within 120 feet, creating a 20-foot tall 5-feet-trajius geyser. Each creature in the Geyser area must make a saving throw of DC 15 dexterity, and must deal 21 (6d6) fire damage on failed saves, or half damage to successful ones. The trembling shakes a rare 60 feet radius around the dragon. Each non-dragon creature on the ground in that area must succeed with a DC 15 dexterity saving throw. Volcanic gas forms clouds in a 20-foot Radius sphere centered around a point that the dragon can see within 120 feet. The sphere spreads out to the corner, and the area becomes lightly obscure. That continues until the initiative counts 20 in the next round. Each creature that initiates a turn in the cloud must succeed with the DC 13 Constitutional Saving Throw or be poisoned until the end of the turn. This way, they are poisoned, but the creatures are neutralised.
Ancient Red Dragon – Basic Rules for 2014
In the 2014 Monster Manual, creature CRs do not increase if encountered in hideouts. It also does not provide additional XP. This is a surveillance revised in the 2025 Monster Manual. Now, for example, when you fight an arch hat in her hideout, if she encounters outside her hideout, the party will pay off 41,000 XP instead of 33,000 XP.
This allows you to balance encounters using the new XP per budget character system from 2024 DMG, rather than relying on a (essentially flawed) CR system.
Group by Group: Lair Action Options
In the 2014 Monster manual, not all the legendary creatures of Lairs acted in hideouts. For example, vampires have legendary behavior and legendary resistance, but their rares contain only some local effects and some information about minions. For creatures who received rare action, different creatures had a variety of options based on their unique nature and typical terrain of their hideout. The theme-based breakdown is as follows:
Dragon's Lairs
The treasure-filled dragon hideaway was (and perhaps before) the best fantasy destination since the Hobbit. However, it is worth noting that only adults and ancient dragons can access hideaway actions to protect the reservoir. Dragons of all ages may be able to blow up enemies with their son's weapons, but only the elder dragons can summon the next effect on their stairs.
The red dragon causes magma to erupt, shaking the ground with a tremble, releasing volcanic gas that poisons the creature. The black dragon draws creatures into the source of their hideout, summoning a herd of insects, spreading the magical darkness. The Gold Dragons can look to the future. The White Dragon summons an ice wall, creating a frozen mist, and drops jagged pieces of ice into its prey.
Undead and Necrotic Entities
Rich regains the spell's slot, detonates the enemy with necrotic damage, and summons the tortured spirit. Mummy Lords can find creatures, gain advantages against turn undead effects, and can block spells.
Mysterious, hidden away from another world
The Sphinx uses surrounding magic to change the flow of time and reroll initiatives, making creatures old and overturning their positions. The viewer covers the surface of the slime, grabs the appendages, and covers the eyeballs. Unicorns extinguish the flames, and native creatures hide and suppress the curse.
Legendary action vs. hideaway behavior

The legendary action allows a monster to act immediately after another creature's turn, but in initiative count 20, there is always a hidden action.
In the 2014 Monster Manual, legendary action was used to increase the frequency of basic attack rolls for creatures like dragon claws and tail attacks, but rare action is a theme, the effect of the whole battlefield provided.
Add a hide action to a creature
If you want to liven up the battle and give creatures that don't normally have them, you should consider the challenge ratings and expected damages per round. If you are using the 2014 ruleset, you can use monster statistics from the challenge rating table as guidelines to ensure that the sum of attacks, legendary actions, and rare effects is consistent with the intended difficulty.
To get an accurate calculation of damage/rounds for Lair action, you may need to calculate the damage output for each round in the first 3 rounds of combat and take an average.
Lair Action Design
The behavior of the hideout must reflect the nature and environment of the creature. Kraken can produce crushed vortices and electrify water. When balancing damage, consider the frequency of Lair actions (usually once per round at initiative count of 20) and whether it affects multiple targets. Environmental dangers, forced movements, or battlefield control effects can have as much impact as direct damage, but these are difficult to consider in monster CR.
Rare is a fun layer
Lair action is a great way to create dynamic battlefields for combat encounters. This will help introduce more strategies into what appears to be legendary combat. Whether it's a volcanic cave of dragons erupting in a burst of lava or a Rich's room pulsating with necrotic energy, these actions ensure that legendary enemies feel as powerful as their reputation suggests. Masu. So don't make your villains stronger – make the grass in their homes a battle worthy challenge!