Gandarvulk, the Walking Volcano, is a powerful Dungeons & Dragons monster. This gargantuan elemental is the first creation from our upcoming book Weapons of Mass Destruction, a collection of high level threats for your D&D characters to face.
Centuries ago, an Efreeti sorcerer named Dis’artres created a massive construct from the remains of fire and earth elementals. She called her creation “Gandarvulk, the walking volcano.” Dis’artres unleashed Gandarvulk on the prime material plane, devastating entire kingdoms before she was defeated by a demigod.
Gandarvulk has laid dormant since its creator’s demise, but the elemental construct is desired by many powerful beings with aspirations of widespread destruction.
Walking Volcano
Gargantuan Elemental Construct, Unaligned
Armor Class 24 (natural armor)
Hit Points 410 (20d20 + 200)
Damage Threshold: 20
Speed 60 ft.
| STR | DEX | CON | INT | WIS | CHA |
| 30 (+10) | 14 (+2) | 30 (+10) | 6 (-2) | 10 (+0) | 6 (-2) |
Saving Throws Dex +10, Con +15, Wis +10
Damage Immunities Necrotic, Poison; Bludgeoning, Piercing, and Slashing from Nonmagical Attacks
Condition Immunities Charmed, Exhaustion, Frightened, Incapacitated, Paralyzed, Petrified, Poisoned, Stunned
Senses Truesight 150 ft., Passive Perception 10
Languages understands Common and Ingan but can’t speak
Challenge 25 (75,000 XP)
Proficiency Bonus +8
Immutable Form. The walking volcano is immune to any spell or effect that would alter its form.
Legendary Resistance (3/Day). If the walking volcano fails a saving throw, it can choose to succeed instead.
Magic Resistance. The walking volcano has advantage on saving throws against spells and other magical effects.
Siege Monster. The walking volcano deals double damage to objects and structures.
Actions
Multiattack. The walking volcano makes one Lava Bomb attack and two Slam attacks.
Lava Bomb. Ranged Weapon Attack: +17 to hit, range 120 ft./240 ft., one target. Hit: 21 (2d10 + 10) bludgeoning damage plus 13 (2d12) fire damage.
Slam. Melee Weapon Attack: +18 to hit, reach 20 ft., one target. Hit: 29 (3d12 + 10) bludgeoning damage, and the walking volcano can push the target up to 20 feet away from it.
Stomp. Melee Weapon Attack: +18 to hit, reach 20ft., one target. Hit: 24 (4d6 + 10) bludgeoning damage. If the target is a creature, it must succeed on a DC 20 Strength saving throw or be knocked prone.
Pyroclastic Flow (Recharge 5–6). The walking volcano releases a current of lava and hot gas in a 120-foot cone. Each creature in that area must make a DC 24 Dexterity saving throw, taking 91 (26d6) fire damage on a failed save, or half as much damage on a successful one.
Legendary Actions
The walking volcano can take 3 legendary actions, choosing from the options below. Only one legendary action can be used at a time and only at the end of another creature’s turn. The walking volcano regains spent legendary actions at the start of its turn.
Move. The walking volcano moves up to half its speed.
Stomp. The walking volcano makes one Stomp attack.
Summon Fire Elemental (Costs 3 Actions). The walking volcano summons a Fire Elemental.
The summoned elemental appears in an unoccupied space within 60 feet of its summoner, acts as an ally of its summoner, and can’t summon other elementals. It remains for 1 minute, until it or its summoner dies, or until its summoner dismisses it as an action.
Destroying the Walking Volcano
Although it is immune to nonmagical attacks, Gandarvulk can be harmed with magic weapons and spells. If Gandarvulk dies, it collapses into a mound of volcanic stones.
Gandarvulk can also be banished. Inside the volcanic crater at the top of Gandarvulk there is a pool of lava that contains a glowing red gemstone. Casting Dispel Magic using a spell slot of 7th level or higher on the stone sends the living volcano back to the elemental plane of fire.
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