Traits

Abyssal Presence. Any creature that starts its turn within 30 feet of the Abyssal Leviathan must make a DC 18 Wisdom saving throw or be frightened for 1 minute. A creature can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success.

Crushing Jaws. The Abyssal Leviathan can bite creatures and objects as large as itself, dealing double damage to structures and vehicles. It automatically grapples (escape DC 20) a creature of Huge size or smaller that it hits with its bite attack.

Deep Sea Terror. While underwater, the Abyssal Leviathan has advantage on Stealth checks, able to use the murky depths to mask its presence.

Multiattack. The Abyssal Leviathan makes two attacks: one with its bite and one with its tail.

Bite. Melee Weapon Attack: +15 to hit, reach 10 ft., one target. Hit: 32 (4d10 + 9) piercing damage, and the target is grappled (escape DC 20). Until this grapple ends, the target is restrained, and the Abyssal Leviathan can’t bite another target.

Tail Swipe. Melee Weapon Attack: +15 to hit, reach 20 ft., one target. Hit: 24 (3d10 + 9) bludgeoning damage, and the target must succeed on a DC 19 Strength saving throw or be knocked prone.

Roar (Recharge 5–6). The Abyssal Leviathan releases a deafening roar in a 60-foot cone. Each creature in that area must make a DC 18 Constitution saving throw or take 45 (10d8) thunder damage and be stunned until the end of the Abyssal Leviathan’s next turn. On a successful save, the creature takes half damage and isn’t stunned.

Swim Speed Boost. The Abyssal Leviathan can use its bonus action to move up to half its swimming speed without provoking opportunity attacks.

Regenerate (Recharge 5-6). The Abyssal Leviathan regains 20 hit points.

Reflective Spines. When the Abyssal Leviathan is hit by a melee attack, it can use its reaction to launch a burst of spines at the attacker. The attacker must make a DC 18 Dexterity saving throw. On a failed save, the attacker takes 21 (6d6) piercing damage, or half as much damage on a successful save.

Defensive Surge. When a creature that the Abyssal Leviathan can see targets it with an attack, it can use its reaction to impose disadvantage on that attack roll. If the attack misses, the Abyssal Leviathan can move up to its speed in a direction of its choice without provoking opportunity attacks.

Lurking Shadows. The Abyssal Leviathan moves up to half its swimming speed while remaining hidden from sight, gaining advantage on the next attack it makes before the end of its next turn.

Tidal Surge (Costs 2 Actions). The Abyssal Leviathan unleashes a wave of water in a 30-foot cone. Each creature in that area must succeed on a DC 19 Strength saving throw or be pushed back 15 feet and knocked prone.

Terrifying Gaze (Costs 3 Actions). The Abyssal Leviathan targets one creature it can see within 60 feet. The target must succeed on a DC 18 Wisdom saving throw or be frightened for 1 minute. A frightened target can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success.

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