Smile Chaos monsters: Swamp Father (5e)
Legends talk about a man who's kids got lost and drown on a cursed swamp. Crazed by sorrow and sadness he kept looking for them day and night for months. Time passed and the dark energies from the swamp corrupted the man transforming him into a fish-like creature. He keeps looking every day and when he finds drowned children the foul energies that corrupted him raise their corpses as undead creatures. The bloated bodies grow sharp fangs and webbed fingers and toes. There are rumors that lately¸ he has been coming out of the swamp to steal children corpses from graveyards to adopt them as part of his new twisted family.