This short sidequest for 5th edition (designed for 4-6 PCs of 5th-9th level) can be placed in any campaign not currently set in an arid location.
The adventurers find the climate becoming unusually hot during a journey, to the point that plants are dying around them. As they continue the normal landscape suddenly turns harsh, dry, and hot, and they encounter a few random fire elementals. At the center of this strange desert is a tower taken over by creatures adhered to flame: an incursion of salamanders, led here by a magical experiment gone awry that left open a portal to the Plane of Fire. The party fights their way to the top before confronting a stream of fiery warriors, only closing the planar gate with the help of a small group of azer—provided they aren't burned alive first!
Designed by Cole Grandel, illustrated by Savage Mojo, and using cartography by Dyson Logos.