Legendary Resistance (6/Day).

If the scion fails a saving throw, it can choose to succeed instead.

Magic Resistance.

The scion has advantage on saving throws against spells and other magical effects.

Siege Monster.

The scion deals double damage to objects and structures.

Actions

Multiattack.

The scion makes one attack using Lava Blade or Lava Ball, as well as two Slam attacks.

Lava Blade.

Melee Weapon Attack: +18 to hit, reach 30 ft., one target. Hit: 32 (4d10 + 10) slashing damage plus 18 (4d8) fire damage.

Lava Ball.

Ranged Weapon Attack: +18 to hit, range 120/480 ft., one target. Hit: 29 (3d12 + 10) bludgeoning damage plus 10 (3d6) fire damage, and the target must succeed on a DC 26 Strength saving throw or have the prone condition.

Slam.

Melee Weapon Attack: +18 to hit, reach 20 ft., one target. Hit: 28 (4d8 + 10) force damage.

Lava Wave (Recharge 5–6).

The scion emits a wave of lava from its blade, hands, or mouth in a 90-foot cone. Each creature in that area must make a DC 25 Dexterity saving throw. On a failed save, a creature takes 60 (11d10) fire damage and has the restrained condition from being embedded in hardening rock. A creature can make a DC 25 Strength (Athletics) check as an action, freeing itself or a creature within reach from the rock on a success. The rock has AC 17 and 40 hit points, and it is immune to fire, poison, and psychic damage. On a successful save, a creature takes half as much damage only.

Bonus Actions

Earth-Shaking Movement.

The scion moves up to its speed and then sends a shock wave through the ground in a 60-foot-radius circle centered on itself. Each creature on the ground in that area that is concentrating must succeed on a DC 26 Constitution saving throw or lose concentration.

Incendiary Smoke.

The scion causes smoke and white-hot embers to billow from its skin, filling a 30-foot-radius sphere centered on itself that moves with it. While the scion's skin billows smoke, ranged attacks against the scion are made with disadvantage. A creature that moves into the smoke for the first time on a turn or starts its turn there must succeed on a DC 25 Constitution saving throw or take 14 (4d6) fire damage. The scion's skin stops billowing smoke after 1 minute, when the scion dies, or when the scion uses this bonus action to stop the smoke.

Regional Effects

The region surrounding a scion of Surtur is altered by the giant's magic, creating one or more of the following effects:

Abundant Ore. Veins of precious metals and ore are more common within 6 miles of the scion.
Desertification. Precipitation is almost nonexistent within 6 miles of the scion, parching the land and withering most plant life.
Empowered Fire Giants. Fire giants within 1,000 feet of the scion gain a +8 bonus to attack and damage rolls.

If the scion dies, existing ore remains, but new veins of ore stop forming. The other effects end immediately.

Scion of Surtur