Copperajah (5e Creature)
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Large elemental, any alignment
Heavy Metal. The copperajah has advantage on saving throws to resist being moved.
Charge. If the copperajah moves at least 20 feet straight toward a target and then hits it with a gore attack on the same turn, the target takes an extra 7 (2d6) piercing damage.
Beast of Burden. The copperajah is considered to be a Huge animal for the purposes of determining its carrying capacity.
Sheer Force. At the start of its turn, the copperajah can gain advantage on all attack rolls it makes during that turn, but attack rolls against it have advantage until the start of its next turn. When the copperajah hits with an attack that has been granted advantage by this feature, the attack deal an additional 7 (2d6) bludgeoning damage.
Gore. Melee Weapon Attack: +8 to hit, reach 5 ft., one target. Hit: 12 (2d6 + 5) bludgeoning damage.
Steelsurge (1/day). Metal spikes emerge from the ground within 30 ft. of the copperajah. All creatures in that space when this happens must succeed on a DC 16 Strength saving throw or take 21 (6d6) piercing damage and be knocked prone. On a successful save, a creature takes half damage and isn't knocked prone. Additionally, the area becomes difficult terrain, and any creature that enters the area must succeed on a DC 15 Dexterity saving throw or stop moving and take 1 piercing damage. Until the creature regains at least 1 hit point, its walking speed is reduced by 10 feet. A creature moving through the area at half speed doesn't need to make the saving throw.