Death Burst: When the spider dies, it explodes in a burst of fiery blood and ooze. Each creature within 5 feet of it must make a DC 13 Dexterity saving throw, taking 7 (2d6) fire damage on a failed save, or half as much damage on a successful one. Flammable objects thataren't being worn or carried in that area are ignited.
Heated Carapace: At the start of each of the spider's turns, it deals 3 (1d6) fire damage to each creature grappling it and each creature or object it is grappling or it is climbing on. A creature that touches the spider or hits it with a melee attack while within 5 feet of it takes 3 (1d6) fire damage.
Spider Climb: The spider can climb difficult surfaces, including upside down on ceilings, without needing tomake an ability check.
Stiffen: If the spider takes cold damage, its heated body stiffens in response, and its speed is reduced to 15 feet until the end of its next turn.
Volcanic Web Walker: The spider ignores movement restrictions caused by webbing, lava, or magma.
Web Sense: While in contact with a web, the spider knows the exact location of any other creature in contact with the same web.