Devil's Snare

• Type: Magical Plant
• Owners: This plant is not owned in a conventional sense. It was utilized by Professor Sprout for educational purposes and by Albus Dumbledore as a magical defence. It was also used as a weapon by Death Eaters.
• Maker: N/A (A naturally occurring magical plant).

Devil's Snare is a dangerous magical plant composed of a mass of soft, springy, snakelike tendrils. It resembles a tangle of dark weeds or vines and characteristically thrives in dark, damp environments, as it has a strong aversion to sunlight and fire. Its tendrils possess the ability to move with purpose, seeking to ensnare any living creature that comes into contact with it. The plant can be deceptively disguised, as seen when a specimen was sent to St Mungo's Hospital for Magical Maladies and Injuries concealed as a potted Flitterbloom.

The primary and most dangerous property of Devil's Snare is its ability to constrict its victims. Upon physical contact, its tendrils immediately begin to coil around a person, starting with their limbs and quickly moving to bind their entire body, including the neck.

• Response to Resistance: The plant reacts to struggle. The more a victim fights and panics, the faster and more tightly the tendrils constrict, which can lead to severe injury, unconsciousness, or even death by suffocation.
• Weaknesses: Devil's Snare has two known weaknesses:
  1. Light and Fire: Its greatest vulnerability is to light and warmth. Bright light, especially sunlight, will cause it to recoil. It is also highly susceptible to fire, and a simple fire-making charm, such as Bluebell Flames or Incendio, will force the plant to shrink back and release its victim. Hermione Granger recalled a rhyme from her Herbology lessons: “Devil's Snare, Devil's Snare, it's deadly fun but will sulk in the sun.”
  2. Relaxation: A less conventional method of escape is for the victim to completely relax their body. When Harry Potter was caught, he was able to stop struggling, and the plant loosened its grip enough for him to fall through its mass. This suggests the plant's hold is dependent on the tension of its victim.

Devil's Snare is a known magical plant studied in the Hogwarts Herbology curriculum. First-year students learn about its properties and weaknesses. In the 1991-1992 school year, Professor Sprout provided a large Devil's Snare specimen to act as one of the magical protections guarding the Philosopher's Stone. When Harry Potter, Ron Weasley, and Hermione Granger dropped through a trapdoor while pursuing Professor Quirrell, they landed in a room filled with the plant. It immediately began to ensnare them. While Harry and Hermione managed to escape—Hermione by conjuring a jet of Bluebell Flames and Harry by relaxing—Ron panicked and had to be freed by Hermione's spell. In 1996, a Devil's Snare was used in an assassination attempt on Broderick Bode, a Ministry of Magic employee recovering at St Mungo's Hospital for Magical Maladies and Injuries. A Death Eater, presumed to be Lucius Malfoy, sent the plant to him disguised as a Christmas gift. A Healer, Miriam Strout, mistook it for a harmless Flitterbloom and placed it on his bedside table, where it strangled him. In 1997, while searching for ways to destroy Salazar Slytherin's Locket, Ron remembered the lessons from his first year, correctly identifying that Devil's Snare “can't stand sunlight,” though this particular weakness was not useful against a Horcrux.

In Harry Potter and the Philosopher's Stone, Devil's Snare serves as the first purely magical obstacle protecting the Stone. Its presence establishes the importance of academic knowledge in practical, life-or-death situations, as Hermione Granger's quick recall from Herbology class is what saves the trio. It also demonstrates an important lesson about bravery and clear-headedness, contrasting Hermione's logical approach and Harry's calmness with Ron Weasley's panic. In Harry Potter and the Order of the Phoenix, the plant's role is transformed from a stationary magical obstacle into a sinister and covert weapon. Its use in the murder of Broderick Bode highlights the insidious methods employed by Lord Voldemort's followers and illustrates how magical knowledge can be twisted for dark purposes.

• In the film adaptation of Harry Potter and the Philosopher's Stone, the Devil's Snare is depicted as a much larger and more aggressive organism, with huge, thick tendrils that actively lash out at the trio. (film)
• Devil's Snare is a common environmental hazard in many of the Harry Potter video games, where it must typically be repelled using a fire spell like Incendio. (video game)
• According to supplementary materials, Devil's Snare can be used as an ingredient in certain potions. (Pottermore)