Pyrogeist (5e Creature)
From D&D Wiki
Medium monstrosity, unaligned
Sense movement. The poltergeist cannot see or hear, but it can sense movement within 60 ft. of it. This means, that a poltergeist cannot know of a creature's location if the creature is not moving.
Glow. The poltergeist sheds dim light in a 30 ft. radius.
Scorching rays. The poltergeist creates up to three ray of fire in available spaces within 50 ft. of it. Each of these rays target a creature within 10 ft. of it. The creature must make a DC 13 Dexterity saving throw or receive 9 (2d8) fire damage or half as much on a successful save.
If there is something known about the pyrogeist, then it is that it is closely related to the poltergeist. Both represent flying orbs and are greatly feared. The pyrogeist, unlike the poltergeist, is able to summon rays of fire, which are similar to the "burner" anomaly. Also, it should be noted that this living ball of fire does not show his actual body upon death, like a normal poltergeist would. Instead, it explodes into pieces. This is theorized to be the result of the differences in pressure between the poltergeist's body and the surrounding air, since the poltergeist instantly cools down when killed.