Old Gods of Appalachia
There are many things to be afraid of in the creeks, rivers, and lakes of Appalachia, but perhaps none so much as a water horse. Its sea-serpent body is 20 feet (6 m) long and has too many fins, too many tails, and perhaps even too many eyes, but it's hard to know, because almost no one sees the entirety of it at once. Some days it's the color of mud half-dried along the bank. Others it's the blue-green of sunlit algae. And some it's darker than the shadow you cast upon the water below you when you lean over to look. Or perhaps it's so big and has so many parts that it's all of these and more.
Although water horses prefer to hunt fish, frogs, and similar creatures, or scavenge remnants from riverbeds, they've been known to bite dogs, sheep, and humans that venture into their territory and pull such creatures underwater if they taste good. Due to their large size, water horses quickly deplete the available food in one area and have to move to a new location every few days.
Water horses are excellent swimmers but can scoot about on land when they need to, including spending a full day or two crawling to get around an obstacle.
Water horses breathe water or air.
Being in deep water hinders a character's attacks by one or two steps; aquatic creatures like the water horse ignore this penalty.
Motive: Hungers for flesh
Environment: Lakes, rivers, creeks, and ponds, alone or in groups of up to three
Health: 15
Damage Inflicted: Moderate wound (5 points)
Armor: 1
Movement: Immediate on land; short when swimming (see below)
Modifications: Speed defense as level 3 due to large size
Combat: A water horse bites once each turn, inflicting damage and firmly holding their target if the creature fails a Might defense roll.
A held creature's Speed defense is hindered, and they automatically take damage at the start of the water horse's turn every round until they break free with a Might- or Speed-based roll. If the attack happens in water, the water horse also swims deeper (moving up to its swimming speed) and wraps its coils around its prey, crushing the air out of them; each round, the grabbed creature must succeed at a Might defense roll or move one step down the damage track due to constriction and suffocation.
About once an hour, a water horse can swim up to a long distance as its action and still make a bite attack. It can reach up to 10 feet (3 m) out of the water, easily plucking someone out of a boat, off a low bridge, or from a campsite near the water line, then dragging its prey back into the water as soon as possible.
Interaction: Water horses are beasts, but they have a strange cunning and sometimes act like they understand human language and behavior. If offered fresh meat (several game birds, a sheep, or a dog), they are likely to snatch the food away and retreat for an hour to eat and digest the meal.
Use: Livestock have gone missing along a deep stream. Something stirs underneath a wooden bridge.
Loot: Water horse teeth and bones might be useful in some kinds of crafting.
Connection: The character grew up hearing stories of a lake monster that would snatch up careless children. The character has a knife or piece of jewelry made from a water horse's tooth.
GM Intrusion: Another water horse appears and bites at a character—preferably one already held by a water horse (easing this attack).