"But Eli, this is just one creature!"
Yes, I realize that this is not a league in the classic sense, but in Pulp Alley there are special rules for what are called Terrors. Terrors are a single model that is powerful enough to take on one or more other leagues. A single terror will often fill the same space on a roster as an entire league. The rules for Terrors also state that the Terror itself is the only permanent member of the league it represents. They may summon creatures and allies, cultists and such if they have the resources to do so, but they are flying solo for the most part.
The Devourer in the Dark is my first Terror. A creature feared by many and not entirely of this world, it hunts sightless, capturing its prey with it tentacles and gulping them down in it wide, toothy maw. It can also squirt a noxious venom, incapacitating its prey. Knobby, scaly hide protects it from harm and its grasping claws allow it to climb the most sheer of surfaces. Most disgusting of all are the undulating, taught blisters that protrude from its back. Some say this is where it traps the souls of its victims, keeping their torment within itself for eternity.