Megalodon (5e Creature)
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Gargantuan beast, unaligned
Water Breathing. The megalodon can breathe only underwater.
Multiattack. The megalodon makes two attacks: one with its bite and one with its tail. It can't make both attacks against the same target.
Bite. Melee Weapon Attack: +11 to hit, reach 10 ft., one target. Hit: 23 (3d10 + 7) piercing damage. If the target is a Large or smaller creature it is grappled (escape DC 16). Until this grapple ends, the megalodon can't bite another target. The megalodon can roll two extra damage if the target is an object or construct composed of wood.
Swallow. The megalodon makes one bite attack against a Large or smaller target it is grappling. If the attack hits, the target is also swallowed, and the grapple ends. While swallowed, the target is blinded and restrained, it has total cover against attacks and other effects outside the megalodon, and it takes 10 (3d6) acid damage at the start of each of the megalodon's turns. A megalodon can have only one creature swallowed at a time.
A typical megalodon measures between 40 and 60 feet long, weighs between 10 and 50 tons and is characterized by its streamlined body and rear-facing teeth. They attack anything that enters their territory, regardless of its size, sentience, or potential deadliness.