Hold Breath. The crocodile can hold its breath for 30 minutes.
Actions
Multiattack. The crocodile makes two attacks: one with its bite and one with its tail.
Bite. Melee Weapon Attack: +8 to hit, reach 5 ft., one target. Hit: 21 (3d10 + 5) piercing damage, and the target is grappled (escape DC 16). Until this grapple ends, the target is restrained, and the crocodile can't bite another target.
Tail. Melee Weapon Attack: +8 to hit, reach 10 ft., one target not grappled by the crocodile. Hit: 14 (2d8 + 5) bludgeoning damage. If the target is a creature, it must succeed on a DC 16 Strength saving throw or be knocked prone.
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