Illumination. The elemental sheds dim light in a 10-foot radius. Heated Body. A creature that touches the elemental or hits it with a melee attack while within 5 feet of it takes 5 (1d10) fire damage. Siege Monster. The elemental deals double damage to objects and structures. Water Susceptibility. For every 5 ft. the elemental moves in water, or for every gallon of water splashed on it, it takes 1 cold damage. If it takes more than 24 cold damage on a single turn, it loses its reaction, and its movement speed is reduced by half until the end of its next turn.
Multiattack. The elemental makes two slam attacks. Slam. Melee Weapon Attack: +8 to hit, reach 10 ft., one target. Hit: 18 (2d8 + 5) 2d8+5 bludgeoning damage + 7 (1d12) 1d12 fire damage. Vulcan Stride. The elemental moves up to its speed in a straight line. During this move, it can enter medium or smaller creatures' spaces. A creature whose space the magma elemental enters must make a DC 13 Dexterity saving throw. On a successful save, the creature is pushed 5 feet to the nearest space out of the elemental’s path. On a failed save, the creature falls prone and takes 7 (2d6) 2d6 bludgeoning damage and 10 (3d6) 3d6 fire damage. Eruption (Recharge 5—6). The elemental erupts a shower of rocks and lava. All creatures other than the elemental within a 20-foot radius of it must succeed on a DC 15 Dexterity saving throw or take 3d6 3d6 bludgeoning damage + 3d6 3d6 fire damage, or half as much on a success.