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Blue Dragon 5e: Stats for Every Age, Lightning Breath and Desert Tactics
A blue dragon breathes the longest line of any chromatic dragon (only the bronze matches it). The adult is a CR 16 Huge dragon with AC 19, 225 hit points (212 in the 2024 rules), a 30-foot burrow speed, and Lightning Breath: a 90-foot line, 5 feet wide, that deals 66 lightning damage (60 in 2024) on a failed DC 19 Dexterity save. Blue dragons are immune to lightning and suit deserts, where they can wait under the sand. The 2024 adult adds spells, including Invisibility at will and a legendary action that turns it invisible and flies it out of reach.
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Blue Dragon Ages Compared
Each age's line is longer than a black dragon's (30 feet against 15 as wyrmlings, 120 against 90 as ancients), and from wyrmling on, a blue dragon can burrow.
Age
CR (XP)
AC
HP (2014 / 2024)
Lightning Breath (Dex save)
Melee per round if all hit (2014 / 2024)
Wyrmling
3 (700)
17
52 / 65
30 x 5 ft line, DC 12, 22 (4d10) / 21 (6d6)
11 / 22
Young
9 (5,000)
18
152 / 152
60 x 5 ft line, DC 16, 55 (10d10)
45 / 51
Adult
16 (15,000)
19
225 / 212
90 x 5 ft line, DC 19, 66 (12d10) / 60 (11d10)
51 / 63
Ancient
23 (50,000)
22
481 / 481
120 x 10 ft line, DC 23, 88 (16d10)
63 / 87
The 2024 edition moved the blue dragon in two directions: tougher as a wyrmling (13 more hit points and twice the melee attacks) and slightly softer as an adult (13 fewer hit points and 6 less breath damage), with spellcasting to make up for it.
Bite.Melee Weapon Attack: +5 to hit, reach 5 ft., one target. Hit: 8 (1d10 + 3) piercing damage plus 3 (1d6) lightning damage.
Lightning Breath (Recharge 5–6).The dragon exhales lightning in a 30-foot line that is 5 feet wide. Each creature in that line must make a DC 12 Dexterity saving throw, taking 22 (4d10) lightning damage on a failed save, or half as much damage on a successful one.
Stat block from the SRD 5.1 (2014 rules) by Wizards of the Coast, licensed under CC-BY-4.0. Check an encounter with this monster in the encounter calculator.
Rend.Melee Attack Roll: +5, reach 5 ft. Hit: 8 (1d10 + 3) Slashing damage plus 3 (1d6) Lightning damage.
Lightning Breath (Recharge 5–6).Dexterity Saving Throw: DC 12, each creature in a 30-foot-long, 5-footwide Line. Failure: 21 (6d6) Lightning damage. Success: Half damage.
Stat block from the SRD 5.2.1 (2024 rules) by Wizards of the Coast, licensed under CC-BY-4.0. Check an encounter with this monster in the encounter calculator.
A 30-foot line at CR 3 is long for a wyrmling. A red or green wyrmling's cone reaches 15 feet, so a blue wyrmling can breathe from twice as far away and still catch two or three characters walking in file. The 22 damage (21 in 2024) on a failed DC 12 save will drop most level 2 or 3 wizards.
The 2024 version is the clearly harder fight: 65 hit points against 52, and two Rends (+5, 11 each) instead of one bite. Against AC 16 each attack hits on an 11 or higher (50%), so it averages 11 damage a round between breaths, double the 2014 wyrmling's 5.5. It also burrows at 15 feet, which lets it hide under loose sand or soil and pick its moment.
Multiattack.The dragon makes three attacks: one with its bite and two with its claws.
Bite.Melee Weapon Attack: +9 to hit, reach 10 ft., one target. Hit: 16 (2d10 + 5) piercing damage plus 5 (1d10) lightning damage.
Claw.Melee Weapon Attack: +9 to hit, reach 5 ft., one target. Hit: 12 (2d6 + 5) slashing damage.
Lightning Breath (Recharge 5–6).The dragon exhales lightning in a 60-foot line that is 5 feet wide. Each creature in that line must make a DC 16 Dexterity saving throw, taking 55 (10d10) lightning damage on a failed save, or half as much damage on a successful one.
Stat block from the SRD 5.1 (2014 rules) by Wizards of the Coast, licensed under CC-BY-4.0. Check an encounter with this monster in the encounter calculator.
Rend.Melee Attack Roll: +9, reach 10 ft. Hit: 12 (2d6 + 5) Slashing damage plus 5 (1d10) Lightning damage.
Lightning Breath (Recharge 5–6).Dexterity Saving Throw: DC 16, each creature in a 60-foot-long, 5-footwide Line. Failure: 55 (10d10) Lightning damage. Success: Half damage.
Stat block from the SRD 5.2.1 (2024 rules) by Wizards of the Coast, licensed under CC-BY-4.0. Check an encounter with this monster in the encounter calculator.
The young blue's breath is a 60-foot line for 55 damage on a failed DC 16 save. That is the same length as an adult black dragon's line, at CR 9. A level 7 party standing in a row down a canyon trail can lose two members to one breath.
In melee, +9 against AC 17 hits on an 8 or higher (65%). The 2014 young blue (bite 21, two claws 12) averages about 29 damage a round; the 2024 version (three Rends of 17) about 33. It has no Legendary Resistance or legendary actions, and its 2024 Constitution save is only +4, so this is the age where control spells and Constitution-save damage spells work best.
Legendary Resistance (3/Day).If the dragon fails a saving throw, it can choose to succeed instead.
Actions
Multiattack.The dragon can use its Frightful Presence. It then makes three attacks: one with its bite and two with its claws.
Bite.Melee Weapon Attack: +12 to hit, reach 10 ft., one target. Hit: 18 (2d10 + 7) piercing damage plus 5 (1d10) lightning damage.
Claw.Melee Weapon Attack: +12 to hit, reach 5 ft., one target. Hit: 14 (2d6 + 7) slashing damage.
Tail.Melee Weapon Attack: +12 to hit, reach 15 ft., one target. Hit: 16 (2d8 + 7) bludgeoning damage.
Frightful Presence.Each creature of the dragon's choice that is within 120 ft. of the dragon and aware of it must succeed on a DC 17 Wisdom saving throw or become frightened for 1 minute. A creature can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success. If a creature's saving throw is successful or the effect ends for it, the creature is immune to the dragon's Frightful Presence for the next 24 hours.
Lightning Breath (Recharge 5–6).The dragon exhales lightning in a 90-foot line that is 5 ft. wide. Each creature in that line must make a DC 19 Dexterity saving throw, taking 66 (12d10) lightning damage on a failed save, or half as much damage on a successful one.
Legendary Actions
The adult blue dragon can take 3 legendary actions, choosing from the options below. Only one legendary action option can be used at a time and only at the end of another creature’s turn. The adult blue dragon regains spent legendary actions at the start of its turn.
Detect.The dragon makes a Wisdom (Perception) check.
Tail Attack.The dragon makes a tail attack.
Wing Attack (Costs 2 Actions).The dragon beats its wings. Each creature within 10 ft. of the dragon must succeed on a DC 20 Dexterity saving throw or take 14 (2d6 + 7) bludgeoning damage and be knocked prone. The dragon can then fly up to half its flying speed.
Stat block from the SRD 5.1 (2014 rules) by Wizards of the Coast, licensed under CC-BY-4.0. Check an encounter with this monster in the encounter calculator.
Challenge 16 (XP 15,000, or 18,000 in lair; PB +5)
Traits
Legendary Resistance (3/Day, or 4/Day in Lair).If the dragon fails a saving throw, it can choose to succeed instead.
Actions
Multiattack.The dragon makes three Rend attacks. It can replace one attack with a use of Spellcasting to cast Shatter.
Rend.Melee Attack Roll: +12, reach 10 ft. Hit: 16 (2d8 + 7) Slashing damage plus 5 (1d10) Lightning damage.
Lightning Breath (Recharge 5–6).Dexterity Saving Throw: DC 19, each creature in a 90-foot-long, 5-footwide Line. Failure: 60 (11d10) Lightning damage. Success: Half damage.
Spellcasting.The dragon casts one of the following spells, requiring no Material components and using Charisma as the spellcasting ability (spell save DC 18):
At Will: Detect Magic, Invisibility, Mage Hand, Shatter
1/Day Each: Scrying, Sending
Legendary Actions
Legendary Action Uses: 3 (4 in Lair). Immediately after another creature’s turn, the adult blue dragon can expend a use to take one of the following actions. The adult blue dragon regains all expended uses at the start of each of its turns.
Cloaked Flight.The dragon uses Spellcasting to cast Invisibility on itself, and it can fly up to half its Fly Speed. The dragon can’t take this action again until the start of its next turn.
Sonic Boom.The dragon uses Spellcasting to cast Shatter. The dragon can’t take this action again until the start of its next turn.
Tail Swipe.The dragon makes one Rend attack.
Stat block from the SRD 5.2.1 (2024 rules) by Wizards of the Coast, licensed under CC-BY-4.0. Check an encounter with this monster in the encounter calculator.
The 2014 adult is a straightforward bruiser: frighten, breathe, bite. The 2024 adult is slippery. It can replace one Rend with Shatter, a 10-foot-radius burst of thunder for 13 (3d8) on a failed DC 18 Constitution save, and its legendary actions let it vanish.
Legendary Resistance (3/Day).If the dragon fails a saving throw, it can choose to succeed instead.
Actions
Multiattack.The dragon can use its Frightful Presence. It then makes three attacks: one with its bite and two with its claws.
Bite.Melee Weapon Attack: +16 to hit, reach 15 ft., one target. Hit: 20 (2d10 + 9) piercing damage plus 11 (2d10) lightning damage.
Claw.Melee Weapon Attack: +16 to hit, reach 10 ft., one target. Hit: 16 (2d6 + 9) slashing damage.
Tail.Melee Weapon Attack: +16 to hit, reach 20 ft., one target. Hit: 18 (2d8 + 9) bludgeoning damage.
Frightful Presence.Each creature of the dragon's choice that is within 120 feet of the dragon and aware of it must succeed on a DC 20 Wisdom saving throw or become frightened for 1 minute. A creature can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success. If a creature's saving throw is successful or the effect ends for it, the creature is immune to the dragon's Frightful Presence for the next 24 hours.
Lightning Breath (Recharge 5–6).The dragon exhales lightning in a 120-foot line that is 10 feet wide. Each creature in that line must make a DC 23 Dexterity saving throw, taking 88 (16d10) lightning damage on a failed save, or half as much damage on a successful one.
Legendary Actions
The ancient blue dragon can take 3 legendary actions, choosing from the options below. Only one legendary action option can be used at a time and only at the end of another creature’s turn. The ancient blue dragon regains spent legendary actions at the start of its turn.
Detect.The dragon makes a Wisdom (Perception) check.
Tail Attack.The dragon makes a tail attack.
Wing Attack (Costs 2 Actions).The dragon beats its wings. Each creature within 15 ft. of the dragon must succeed on a DC 24 Dexterity saving throw or take 16 (2d6 + 9) bludgeoning damage and be knocked prone. The dragon can then fly up to half its flying speed.
Stat block from the SRD 5.1 (2014 rules) by Wizards of the Coast, licensed under CC-BY-4.0. Check an encounter with this monster in the encounter calculator.
Challenge 23 (XP 50,000, or 62,000 in lair; PB +7)
Traits
Legendary Resistance (4/Day, or 5/Day in Lair).If the dragon fails a saving throw, it can choose to succeed instead.
Actions
Multiattack.The dragon makes three Rend attacks. It can replace one attack with a use of Spellcasting to cast Shatter (level 3 version).
Rend.Melee Attack Roll: +16, reach 15 ft. Hit: 18 (2d8 + 9) Slashing damage plus 11 (2d10) Lightning damage.
Lightning Breath (Recharge 5–6).Dexterity Saving Throw: DC 23, each creature in a 120-foot-long, 10-foot-wide Line. Failure: 88 (16d10) Lightning damage. Success: Half damage.
Spellcasting.The dragon casts one of the following spells, requiring no Material components and using Charisma as the spellcasting ability (spell save DC 22):
Legendary Action Uses: 3 (4 in Lair). Immediately after another creature’s turn, the ancient blue dragon can expend a use to take one of the following actions. The ancient blue dragon regains all expended uses at the start of each of its turns.
Cloaked Flight.The dragon uses Spellcasting to cast Invisibility on itself, and it can fly up to half its Fly Speed. The dragon can’t take this action again until the start of its next turn.
Sonic Boom.The dragon uses Spellcasting to cast Shatter (level 3 version). The dragon can’t take this action again until the start of its next turn.
Tail Swipe.The dragon makes one Rend attack.
Stat block from the SRD 5.2.1 (2024 rules) by Wizards of the Coast, licensed under CC-BY-4.0. Check an encounter with this monster in the encounter calculator.
The ancient blue breathes a 120-foot line, 10 feet wide, for 88 damage on a DC 23 Dexterity save. A character needs at least a +4 Dexterity save just to have a 10% chance of halving it (a natural 20 is not an automatic success on a save). It burrows at 40 feet.
Both editions give it 481 hit points. The 2024 ancient hits much harder in melee (three Rends of 29 against a 2014 total of 63), casts Shatter at level 3 (18 damage, 4d8, DC 22), and has 4 Legendary Resistances a day, 5 in its lair.
How Blue Dragons Fight
A blue dragon fights at range and on its terms: breath down a line from far away, then out of reach, then back.
Line up the party. A 90-foot line only pays off when several characters stand in it. Desert terrain does that work: canyon floors, dune ridges, caravan trails and narrow stone stairs into a ruin all put the party in a row. An adult that flies to one end of a canyon and breathes down it can catch everyone.
Breath recharge. Lightning Breath recharges on a 5 or 6 at the start of the dragon's turn, so the odds of having it back are 1 in 3 each round. In a fight lasting four rounds the dragon averages two breaths. A character with a +2 Dexterity save fails the adult's DC 19 on a 16 or lower (80%) and takes an expected 0.8 x 66 + 0.2 x 33, about 59 damage (54 against the 2024 breath).
Burrow and wait. A blue dragon can dig into loose sand at its burrow speed (30 feet for an adult) and wait for the party to walk over it. It has no tremorsense, but its blindsight (60 feet for an adult) arguably lets it perceive creatures within range while buried; beyond that, what it notices is your call. The usual play is simple: it hears the caravan, surfaces behind it and breathes down the line of camels.
The 2014 adult in melee. Frightful Presence (DC 17 Wisdom) on the first round, then bite and claws at +12, which hit AC 19 on a 7 or higher (70%) for about 36 damage a round. The tail reaches 15 feet, so its legendary Tail Attacks punish anyone who backs off to 10 feet. Its Wing Attack (DC 20 Dexterity, 14 damage and prone) clears melee and lets it fly 40 feet.
The 2024 adult disappears. Cloaked Flight casts Invisibility on itself and flies it up to 40 feet, once per round, right after another creature's turn. That timing matters:
•The dragon goes invisible after the fighter's turn. The wizard and cleric who act next can't see it, so they can't target it with most spells, and attacks against it have disadvantage.
•On its own turn, its first Rend has advantage because it is Invisible. The spell ends immediately after that attack roll, so only the first attack benefits.
•After the next player's turn, it uses Cloaked Flight again.
Sonic Boom adds a Shatter after another creature's turn, and Tail Swipe adds a Rend. Run all three in a round, with Cloaked Flight last (casting Shatter or attacking ends the invisibility), and the dragon deals thunder damage to a clump of casters, rends whoever is closest, and starts its turn invisible.
Sending and Scrying set up the ambush. Once a day each, the 2024 adult can watch the party (Scrying) and message its servants anywhere (Sending). A blue dragon that runs a desert as its territory should know the party is coming before they reach the canyon.
When to leave. A blue below half hit points goes invisible and flies off, or burrows. Both leave the party with nothing to hit.
Running a Blue Dragon Encounter
The 2024 XP budget (SRD 5.2.1) for four characters:
Age
XP
Four characters of level
Low / Moderate / High budget
Difficulty
Wyrmling
700
3
600 / 900 / 1,600
Moderate
Young
5,000
7
3,000 / 5,200 / 6,800
Moderate
Adult
15,000 (18,000 in lair)
13
10,400 / 16,800 / 21,600
Moderate (High in lair)
Ancient
50,000 (62,000 in lair)
20
25,600 / 52,800 / 88,000
Moderate (High in lair)
Under the 2014 Dungeon Master's Guide guidelines (used by our encounter calculator), a solo adult blue is Hard for four level 13 characters (Hard 13,600, Deadly 20,400) and Medium for four level 15 characters.
A blue dragon's fight is easier to balance than a red's because the line hits fewer people, and harder to run because the dragon should rarely stand still. Plan the map first: where does it burrow, where does it breathe from, where does it fly when it vanishes? Servants that hold the party in place help it most: a war band of gnolls that pins the caravan in a canyon makes a perfect line for the breath.
How Players Beat a Blue Dragon
•Spread out sideways, never in file. Two characters with at least 5 feet of open ground between them can't both be hit by a 5-foot line. Against the ancient's 10-foot-wide line, leave at least 10 feet.
•Don't use lightning. All ages are immune. Lightning Bolt and Call Lightning won't touch it.
•See the invisible (2024).Faerie Fire outlines the dragon, and outlined creatures can't benefit from being Invisible. A character with blindsight or truesight ignores the invisibility completely. Without either, use area spells on its last known position.
•Ready attacks for the moment it surfaces. A burrowed or invisible dragon that attacks reveals itself. Characters who Ready an attack for "when it appears" get to hit it before it vanishes again.
•Hit its Constitution and Charisma (2024). The 2024 adult's Con +6 and Cha +5 are far below the 2014 version's +11 and +9. After its Legendary Resistance is spent, Banishment is a coin flip at DC 17 (it fails on 11 or lower, 55%).
•Counter the vanishing act. Invisibility needs verbal and somatic components, so Counterspell can stop Cloaked Flight. In the 2024 rules the dragon resists with a Constitution save.
•Protect against lightning. Protection from Energy (lightning) halves the breath for one character, and Haste gives advantage on Dexterity saves.
Blue Dragon Lair Rules in the SRD
For the adult and ancient blue dragon, SRD 5.2.1 lists exactly three lair effects, all numeric: XP increases (18,000 for the adult, 62,000 for the ancient), Legendary Resistance becomes 4/day for the adult and 5/day for the ancient, and both get 4 legendary action uses instead of 3. It gives no lair actions, regional effects or description of the lair.
SRD 5.1 has no blue dragon lair actions and no general lair-action rules. Desert lair actions and regional effects for blue dragons appear in the Monster Manual, not the SRD. This page doesn't reproduce them.
Blue Dragon Encounter Ideas
The toll collector (2024). Every caravan master on the salt road receives the same short message, delivered by Sending: the size of this season's toll and the name of the oasis where it's to be left. The adult blue dragon behind it has used the road for decades. Most merchants pay. One didn't, and the party is guarding his replacement caravan.
The sunken watchtower. A sandstorm has uncovered half of an old stone watchtower. Its stairway drops 60 feet in a straight shaft to a buried courtyard, and a young blue dragon has claimed the courtyard as its den. The only entrance is a straight, narrow stairway, and the young blue's line is exactly 60 feet long.
The oasis. A blue dragon wyrmling has buried itself under the sand at the edge of the only water for two days in any direction. Travelers who come to drink lose their animals at night. The wyrmling is young enough to be bargained with, and old enough to know where the nearest adult blue dragon hunts.
A blue dragon wyrmling is CR 3, a young blue dragon CR 9, an adult blue dragon CR 16 and an ancient blue dragon CR 23. The 2014 and 2024 rules use the same CRs.
How long is a blue dragon's breath weapon?
Lightning Breath is a 5-foot-wide line: 30 feet long for a wyrmling, 60 feet for a young dragon and 90 feet for an adult. The ancient's line is 120 feet long and 10 feet wide. Creatures in the line make a Dexterity save and take half damage on a success.
Can blue dragons burrow?
Yes. Every age has a burrow speed: 15 feet for the wyrmling, 20 feet for the young dragon, 30 feet for the adult and 40 feet for the ancient.
Is a blue dragon immune to lightning?
Yes. All blue dragons are immune to lightning damage in both editions, with no other damage immunities, resistances or condition immunities.
Can a 2024 blue dragon turn invisible?
The 2024 adult and ancient blue dragons cast Invisibility at will, and their Cloaked Flight legendary action casts it on themselves and lets them fly up to half their fly speed. The invisibility ends right after the dragon makes an attack roll, deals damage or casts a spell.
Blue dragon vs red dragon: which is stronger?
The red dragon has the higher CR and more hit points at every age, and its cone catches more characters. The blue's line reaches much farther, and its burrowing (and the 2024 version's invisibility) makes it harder to pin down.
Stat blocks: System Reference Document 5.1 (2014) and 5.2.1 (2024), Wizards of the Coast, CC-BY-4.0. Tactics, encounter math and ideas are Loreify's own.
This page includes material from the System Reference Document 5.1 and 5.2.1 by Wizards of the Coast LLC, available under the Creative Commons Attribution 4.0 International License. Loreify is not affiliated with Wizards of the Coast.