Yellow dragon
From Ardrana
Yellow dragons are dragons of the desert. Their scales are the grayish-yellow of desert sands, with a dusty texture to them, They are solitary and secretive, preferring to lay in wait for prey to stumble into carefully-prepared traps instead of hunting actively.
Yellows are solitary, selfish creatures that form no close bonds with any other creature, including other yellows. They are highly territorial; the only time they'll let another yellow into their territory is to mate. At birth, yellows have soft, tan scales. As they grow older, the scales harden and become lighter in color.
Yellow dragons love deserts, preferring areas of sandy, windswept desolation. They are most comfortable in daytime temperatures of 105 degrees and up, although they can easily survive subfreezing temperatures at night. They share much the same territory as brasses; thus the species occasionally come into conflict.
Although preferring guile to combat and ambush to attack, yellows are fierce and cunning fighters. Even if forced into a situation where direct combat is inevitable, they'll still use their spells and innate abilities so as to mislead, misdirect, and distract their opponents. A yellow dragon's breath weapon is a high-velocity blast of scorching air mixed with sand.
A favorite hunting tactic for a yellow is to dig a steep-walled, cone-shaped depression in the sand, and then bury itself at the bottom of this crater with just its eyes and nostrils showing. When a creature stumbles into the depression, the dragon moves its wings in the sand, causing the steep walls of the cone to collapse and drawing the prey straight to the dragon's mouth.
Although able to eat anything, yellows favor fresh meat. (Demi-humans are considered a delicacy, as are the unhatched eggs of brass dragons. (Yellows rarely get to enjoy this latter feast.)
Note: Yellow dragons originally appeared in this form in the 2nd Edition Monstrous Manual for the AD&D game from TSR. Their use here is for the purposes of providing context for the campaign only.