Large beast, unaligned

Armor Class 14 (natural armor)
Hit Points 76 (9d10 + 27)
Speed 40 ft., swim 20 ft.

21 (+5) 7 (–2) 16 (+3) 2 (–4) 11 (+0) 4 (–3)

Skills Athletics +7, Intimidation +1
Senses passive Perception 10
Challenge 3 (700 XP)
Proficiency Bonus +2


  • Hold Breath. The hippopotamus can hold its breath for 10 minutes.


  • Gore. Melee Weapon Attack: +7 to hit, reach 5 ft., one target. Hit: 18 (3d8 + 5) piercing damage.
  • Thunderous Bray (Recharge 5–6). The hippopotamus emits a resounding bray in a 15-foot cone. Each creature in that area must make a DC 13 Constitution saving throw. On a failure, a creature takes 14 (4d6) thunder damage and is incapacitated until the end of its next turn. On a success, a creature takes half the damage and isn’t incapacitated.


The boulder-sized creature waddles out of the water, and strolls down the riverbank. Suddenly, it rushes forward, swift as a horse despite its massive bulk. Its jaws swing open, revealing curved tusks and bone-crushing molars.

A hippopotamus is a massive, aquatic herbivore with a truly terrible attitude. Hippopotamuses are territorial and reflexively aggressive, often chasing down and killing humanoids in their territory. Their massive, powerful jaws work with long, curved tusks, and their enormous bodies are resistant to attack. They are social creatures, often gathering in sieges of up to thirty members. They eat short grasses along riverbanks as well as aquatic plants.

Misleading Appearance. Hippopotamuses seem cute and sedentary at first glance. They’re pleasantly rotund, vocalize constantly, and look slow, harmless, and focused on eating grass. Unfortunately, they can run fast, their bite crushes bone, and they view any infringement on their territory as an invitation to murder. The largest weigh up to 6,000 pounds.

River Monsters. The rivers are never safe in hippopotamus territory. Though slow swimmers, they often sink deep beneath the water then ambush swimmers or small boats in lethal attacks. While not stealthy, the muddy waters they call home easily conceal even the largest hippopotamus, leaving little sign of their presence. River boat captains in hippo territory know to turn around if they spot wiggling ears emerging from the water’s surface.

Failed Domesticates. There have been many attempts to domesticate hippopotamuses, either as beasts of burden or livestock. Some druids have made them loyal through nature magic, but even these hippos are compliant only as long as the magic continues. The symbiotic relationships and long-term loyalty druids enjoy with other animals are pointedly missing. Mundane attempts at domestication have universally failed, occasionally with unfortunate side effects. Hippos introduced to river and marshlands far beyond their natural range by would-be ranchers or ambitious warlords keeping them as “pets” have made the waters more dangerous for anyone traveling there.

Divine Ascension. Some hippopotamuses ascend to a divine state upon their deaths, gaining gold markings on their hide and often growing to even greater size. Scholars have yet to pinpoint the reason particular hippopotamuses are chosen for ascension. These sacred hippopotamuses are divine guardians of temples and holy sites in areas where hippopotamuses are common; sometimes priests live in harmony with sacred hippos in these temples and shrines, though just as often the site is abandoned or remote. The divine blessings do nothing to change the animals’ territorial attitudes.

Sacred Protectors. Sacred hippos recognize and are much less aggressive toward priests of their deity and pilgrims to the sacred site they are tasked to protect. Sacred hippopotamuses serving good-aligned deities may even provide pilgrims food and guidance along their journey before returning to guard duty. Anyone who threatens a pilgrim in a sacred hippopotamus’s presence, no matter how minor or justified the offense is, can expect swift retribution. In rare cases, temple acolytes may confront the hippopotamus and if a young acolyte is particularly rude to a pilgrim.

Worryingly Clever. All hippos can be clever, but sacred hippos know exactly how to exploit their abilities against potential foes. They might lure trespassers into natural hazards, set off a temple’s traps to snare trespassers, or ambush trespassers from hidden rooms, sacred pools, or shaded alcoves.

Section 15: Copyright Notice

Tome of Beasts 3 © 2022 Open Design LLC; Authors: Eytan Bernstein, Celeste Conowitch, Benjamin L. Eastman, Robert Fairbanks, Scott Gable, Basheer Ghouse, Richard Green, Jeremy Hochhalter, Jeff Lee, Christopher Lockey, Sarah Madsen, Ben Mcfarland, Jonathan Miley, Kelly Pawlik, Sebastian Rombach, Chelsea Steverson, Brian Suskind, Mike Welham

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