This is what 2 steps tall, yellow-eyed toads are called. These mystical animals are as rare as they are dangerous. In their insatiable hunger, they pounce on any life form that crosses their path and is not twice as massive as themselves. To kill its victim, the swamp turtoll sprays it with a viscous, highly corrosive acid, which is capable of destroying even the iron of armour.
The Swamp turtoll does do not reproduce and never seem to die of old age. They are known to almost all races, and almost every one of them explains their origin differently. The most common story among humans is that they were once servants of a powerful sorcerer, but at the end of his life he cursed them to an eternal existence as monsters, that they might forever guard his underground castle.
If this story is true, these servants do not seem to take their mission very seriously. After all, the individual swamp turtoll - there are just a dozen of them - live all over the world.