The Spring-Heeled Jack is a mysterious species of fey native to the First World who occasionally travels to the Material Plane to go on murder sprees. Due to their rarity and distrust of each other's company, Spring-Heeled Jacks have never been seen together, giving rise to the misconception that Spring-Heeled Jack is a singular, unique individual.
Spring-Heeled Jacks are hairy horned humanoids with cruel glowing eyes, cloven hooves and a pointed tail. They tend to wear tattered cloaks to disguise themselves at night; while these disguises are crude, the Spring-Heeled Jack only needs its victim to put their guard down enough to move within striking distance (which is longer than it might seem). Once prey is in range, the Spring-Heeled Jack instantly leaps a great distance to strike with a knife which it calls Little Love, giving the species its name. A Spring-Heeled Jack is about 4 feet tall and weighs 80 pounds.
While Spring-Heeled Jacks are native to the First World, they prefer to murder victims on the Material Plane, where the concept of death is more permanent, and their crimes are more 'appreciated'. Spring-Heeled Jacks are almost always seen at night in or near a large city. When going to ground, they often lurk in the wilds, where most trackers cannot find them. Hunters sometimes find grotesquely mutilated animal carcasses, never suspecting that a Spring-Heeled Jack is responsible.
A Spring-Heeled Jack, when travelling to the Material Plane, starts a killing spree and quickly becomes one of the most wanted criminals in the local community, who swiftly acts to arrest 'him'. After a particularly violent murder, the Spring-Heeled Jack vanishes for a few weeks before revealing itself again.
Sometimes, a Spring-Heeled Jack might decide to let its prey live to tell the tale. They enjoy their dreaded reputation, and occasionally eavesdrop on people to learn about these rumours, even whispering rehearsed lines to victims before killing them.
Negotiation with a Spring-Heeled Jack is all but impossible; one can only distract them by pointing out more exciting quarries. Spring-Heeled Jacks flees for the roofs if they find their opponent too powerful, much to the frustration of law enforcement.
Spring-Heeled Jack sightings are most common in Ustalav. Sightings that across centuries are attributed to Jack's long lifespan and ability to travel quickly, or the belief that it is a mere urban legend that does not actually exist. No one has actually guessed that Spring-Heeled Jack is, in fact, an entire species of creature.
- Adam Daigle and Patrick Renie. (2011). Bestiary. The Haunting of Harrowstone, p. 88. Paizo Publishing, LLC. ISBN 978-1-60125-308-8
- Ron Lundeen. (2021). Spring-Heeled Jack. Monsters of Myth, p. 94. Paizo Inc.. ISBN 978-1-64078-389-8
- Adam Daigle and Patrick Renie. (2011). Bestiary. The Haunting of Harrowstone, p. 89. Paizo Publishing, LLC. ISBN 978-1-60125-308-8