Black Dragon
The black dragon is one that can easily strike fear into a D&D character's heart. Often referred to as a "skull dragon," the black dragon has a skeleton-like face that is accentuated by the deteriorated hide around the cheekbones and horns. These dragons are obsessed with coins, often the currency of choice in the D&D worlds, and they will often capture humanoid characters and interrogate them about the whereabouts of stockpiles of old or silver coins so that they can attack and take them. Even with the information they seek, they usually go ahead and kill the victim anyway. Their alignment is always chaotic evil. Black dragons grow up to 60 feet in length, and can fly short distances and inflict major damage to foes using a stream of acid that projects from their mouths. These dragons are sometimes able to charm reptiles and sometimes speak with animals.
Brass Dragon
The brass dragon is not as scary in appearance as many of its peers. This chaotic good species is also less likely to injure or kill the player party without good cause. The brass dragon's scales have a warm burnished brass color and its eyes are like orbs of molten metal. This species of dragon is charismatic and enjoys conversation. It is not typically interested in a fight, which is good news for those who run upon it, because it can still do serious damage with its fire breath weapons and its ability to put those around it to sleep. In fact, if someone interests the brass dragon and is not willing to stick around for some small talk, it is not unusual for the dragon to use its sleep weapon to knock out a person, and then pin them down or bury them neck deep in the dirt until they wake up and force conversation. Older dragons of this kind can also control the weather in their immediate area through magic, and ancient brass dragons can summon a djinni, or genie.
Copper Dragon
With a copper to green skin and glowing turquoise eyes, the copper dragon looks more menacing than it is. This species of dragon is actually a good-natured one, although dangerously unpredictable -- that is if you don't have a good sense of humor. The copper dragon likes to have fun. It will almost never do harm to anyone who can tell a good joke, come up with a new riddle or just spin a humorous yarn. But those who aren't willing to cut loose and joke around, or who don't appear to find the dragon's jokes funny, can be in for trouble. This chaotic good dragon will only take so much disrespect in this manner. Eventually, the dragon may use its ability to turn rock into mud and trap the party in the mud. Or in a fit or aggravation, it may grab the party and fly them into the air and crush them into the walls of a canyon.
Tiamat
No conversation about D&D dragons is complete without the mention of the most powerful evil dragon in D&D lore. Tiamat is known as the chromatic dragon, and is feared by all and worshiped by some as a god. She is the five-headed queen of all evil dragons. Each head is a different color -- white, black red, blue and green. She believes that she is the ruler of all living things, as well as all gods. She wages a permanent war against all good dragons and good deities. Tiamat is considered among the most powerful possible enemies in all of Dungeons and Dragons gaming.