Diplodocus (5e Creature)
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Gargantuan beast (sauropod), unaligned
Multiattack. The diplodocus makes 3 kick attacks. It may substitute two kick attacks with one tail or stomp attack, but can't use the kick and tail/stomp against the same target.
Kick. Melee Weapon Attack: +11 to hit, reach 5 ft., one target. Hit: 18 (2d10 + 7) bludgeoning damage. If target is a creature, it must succeed on a DC 17 Strength or Dexterity saving throw or be knocked prone.
Stomp. Melee Weapon Attack: +11 to hit, reach 5 ft., one prone target. Hit: X (4d10 + 7) bludgeoning damage.
Tail. Melee Weapon Attack: +11 to hit, reach 25 ft., one target. Hit: X (2d10 + 7) bludgeoning damage plus X (1d8 + 7) slashing damage and X (2d6) thunder damage.
Tail Crack. When 3 creatures move into range of the diplodocus, it may use its reaction to crack its tail. Each creature that can hear within 30 feet of the diplodocus must succeed a DC 17 Constitution saving throw. If a creature fails, it takes X (2d12 + 7) thunder damage and is deafened. If it succeeds, it takes half damage and is not deafened.
Diplodocus is a humongous dinosaur with a long neck that lets it browse from trees and an almost comically long tail, as long as both its neck and body combined. This tail is thin and whip-like, which is able to stroke targets fast enough to produce a sonic boom. On top of this, it is also covered in sharp, strong osteoderms, which match those running along the midline of its back. Due to its massive size and strong tail, all but the toughest predators will take their chances against it, and adventurers in the jungles of Chuult and the lands of Arkamata should be wary.