Jade Dragon [Mystara]

From 120 feet or more, a jade dragon is indistinguishable from a green dragon, though an expert might notice it is a bit smaller and stockier, with a shorter, thicker tail. Up close, its translucent scales glitter and give it away. It speaks its own language and the common tongue of gem dragons.

Its breath is a reeking swirl of brown, yellow and green gas. First, it acts as a green dragon's chlorine blast, dealing damage by age, halved with a successful save vs. breath weapon. A victim who fails that save must then save vs. poison or contract a rotting disease. Only cure disease helps a living victim; no other healing spell or item works. The disease deals 1 point per turn, and repeated infections do not stack, so a character who fails three times still loses only 1 point per turn until cured, if he lives that long. It also rots away every nonmetal item the victim carries within 1d6 turns (magic items save vs. acid) unless cure disease is cast on them first.

Jade dragons live in woodlands and among the friendliest, most talkative dragons on the planet. They see themselves as refined and sophisticated and love philosophical debate with creatures of any alignment, mainly to display a wisdom they themselves rate as immense. They collect art above all, and offering a new piece, or interesting facts about one already in the hoard, can win their favor and distract even a hungry one.

It eats both meat and plants, hunting all kinds of forest animals and also eating vegetation, with young saplings and bamboo its favorites.