Elasmotherium (5e Creature)
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Huge beast, unaligned
Trampling Charge. If the elasmotherium 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 13 (2d12) bludgeoning damage. If the target is a creature, it must succeed a DC 18 Strength saving throw or be knocked prone. If the target is knocked prone, the elasmotherium can make one stomp attack against it as a bonus action.
Rampage. When the elasmotherium reduces a creature to 0 hit points with a melee attack on its turn, the rhinoceros can take a bonus action to move up to half its speed and make a gore attack.
Gore. Melee Weapon Attack: +10 to hit, reach 10 ft., one target. Hit: 23 (3d12 + 7) piercing damage.
Stomp. Melee Weapon Attack: +10 to hit, reach 10 ft., one prone creature. Hit: 29 (4d10 + 7) bludgeoning damage.
The elasmotherium is a massive rhinoceros native to grasslands, commonly seen among the similarly sized mammoths. When aggravated, it lunges toward its aggressor in a thundering, horse-like gallop, and spears them with a singular, spear-like horn atop its head.