Emerald dragons

Emerald dragons are reclusive dragons with a lawful bent. They are inquisitive about history, but also paranoid and distrustful of visitors, whom they deter by setting traps in and by their lairs, and with their breath weapon, a powerful blast of wind. They have scales in many shades of green, with a scintillating appearance that makes the dragon seem to be in constant motion.

Despite their isolationist tendencies, when gem dragons do interact with other creatures, they can be scintillating hosts and conversationalists. They have a way with making their guests feel at home and relaxed, such that

the dragons can often convince a guest of ideas they would never ordinarily entertain.

Gem dragons are all inherently psionic creatures. They develop telepathic abilities shortly after hatching—sometimes even before—that grow in strength as they age. Some hone these mental powers further, manifesting powerful magical abilities through their minds.

These psychically adept dragons often find themselves at odds with aberrations, particularly mind flayers and aboleths. The gem dragons are skilled at locating areas where the Far Realm intrudes upon the Material Plane and set themselves against the alien creatures spawned or twisted in such places.

Physical description

Emerald Dragons are a surprisingly swift race, moving fast, often teleporting through the Dream to wherever their thoughts lead. As a result they are the least interested about happenings in the material plane and often must have any major events brought to their attention by other Gem Dragons. When they venture to the physical world, they act as though it is the illusion and the realm from which they hail is the only source of reality, often only appearing as an illusion in half ethereal forms, or not physically at all. 

When they're young, their scales are a dark-green, which ultimately is also their greatest disguise since they fit into the background. As they grow old their bright green scales directly reflect the sunlight and they lose all sense of camouflage.

Combat

Emerald dragons can breath a cone of sonic energy. They can also generate a cloud of fog to blind opponents.

Lair

Gem dragons set themselves apart from the affairs of other beings, even their own kind. They search out lairs far from established populations which they can tend in solitude, or so they can carefully cultivate a circle of servants or vassals to tend their interests in the surrounding region.

Gem dragons break their natural inclination to solitude to mate and protect their clutches of eggs, but rarely for any other reason.