When you’re exploring the vast and mysterious oceans of Dungeons & Dragons, you’re bound to encounter some truly monstrous inhabitants. From the slithering to the colossal, these underwater D&D monsters can turn a simple voyage into a desperate fight for survival. We’re diving deep to count down the ten most terrifying creatures that lurk beneath the waves.
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10. The Haunting Sea Spawn
These unfortunate souls, their bodies encrusted with coral and barnacles, are a low-level party’s nightmare. With a Challenge Rating (CR) of 1, an Armor Class (AC) of 11, and 32 hit points (HP), Sea Spawn may seem manageable. However, their multiattack, which includes two unarmed strikes plus a bite, poison quill, or tentacle attack, averages around 9 HP damage with a chance of poisoning. For new adventurers, a swarm of these can quickly overwhelm.
9. The Deceptive Deep Scion
More robust than the Sea Spawn, the Deep Scion (CR 3, AC 11, 67 HP) can infiltrate the surface world by shapeshifting into their former human selves. Loyal only to their monstrous masters, these spies are perfect for psychological horror. In their aquatic form, they can deal an average of 18 HP with two battleaxe attacks or 20 HP with bite and claw attacks. Their psychic screech can stun, making them formidable foes.
8. The Fanatical Kraken Priest
Don’t let the “priest” in Kraken Priest (CR 5, AC 15, 75 HP) fool you; these spellcasters are anything but pacifists. Driven to worship the very embodiment of terror, their bodies grotesquely mutate with ink-black eyes or dribbling mouths. Their spellcasting, combined with thunderous touch or thunderbolt multiattacks, can unleash up to 54 HP of average damage per turn, often prophesying your doom.
7. The Unsettling Froghemoth
Emerging from murky swamps, the Froghemoth is an elephant-sized monstrosity (CR 10, AC 14, 161 HP) with four tentacles, thick rubbery skin, and an appetite for unsuspecting adventurers. It can breathe both air and water, and its three eyestalks give it near 360-degree vision. With three attacks per turn, including devastating tentacle and bite attacks, it can inflict an average of 60 HP damage, making it a truly painful encounter.
6. The Corrupting Wastrilith
Hailing from the Abyss, Wastriliths (CR 13, AC 18, 157 HP) are fiends that pollute any water they inhabit. These cruel overlords can command corrupted water to prevent escape or drag victims within reach. Drinking their tainted water can lead to death or transform you into a thrall of chaos. With a bite and two claw attacks, they can deal about 70 HP in average damage, making them incredibly dangerous aquatic D&D monsters.
5. The Mighty Dragon Turtle
The aptly named Dragon Turtles (CR 17, AC 20, 341 HP) are truly fearsome ocean dwellers, rivaling true dragons in size and ferocity. Their deadly jaws, steaming breath, and crushing tails make them a force to be reckoned with. Intelligent and fond of treasure gained from sinking ships, these behemoths are incredibly hard to hit. They get up to three attacks for an average of 58 damage, and their steam breath can average 52 damage on a failed DC 18 Constitution save.
4. The Ancient Aboleth
Before the gods, Aboleths (CR 10, AC 17, 135 HP) ruled the primordial oceans, enslaving early life forms with their powerful minds. These masters of telepathy can control minds and gain knowledge by consuming creatures. With three tentacle attacks averaging 36 HP, a tail attack for 15 HP, and the ability to enslave on a failed DC 14 Wisdom save, these cunning underwater D&D monsters punch well above their Challenge Rating, especially with their lair and legendary actions.
3. The Destructive Olhydra
The Princess of Evil Water, Olhydra (CR 18, AC 18, 324 HP), appears as a huge cresting wave or a shapeless watery mass. She uses powerful water manifestations to destroy vessels and settlements, claiming pirates and raiders as her own. With two slam or water jet attacks dealing 42 HP average damage, the ability to summon elementals, and legendary actions like crushing and turning water to acid, confronting Olhydra alone is a recipe for disaster.
2. The Colossal Leviathan
Almost a literal force of nature, the Leviathan (CR 20, AC 17, 328 HP) is an immense serpent-like creature from the Elemental Plane of Water. It can be summoned to sink ships and devastate coastal communities. Dealing double damage to objects and structures, this watery elemental can enter another creature’s space. Its multiattack deals an average of 63 damage, and it can create a magical tidal wave up to 250 feet tall, inflicting 45 average damage and knocking you prone.
1. The Apex Predator: The Kraken
The undisputed king of underwater D&D monsters, the Kraken (CR 23, AC 18, 472 HP) is a primeval force that inspires panic in nations and crushes warships. These legendary beasts can raise or calm storms and even crawl up rivers to nest in freshwater lakes. With three tentacle attacks doing an average of 60 HP damage (and the ability to throw you 60 feet), a bite for 23 HP (with a swallow option), a lightning storm, and an ink cloud that can poison, the Kraken is the ultimate aquatic terror in D&D. Its lair actions, which include creating strong currents and charging water with electricity, only amplify its devastating power.
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What do you think, adventurers? Did your most terrifying underwater D&D monsters make the cut? Let me know your favorites in the comments!
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