the rarest dragon on dragon vale would have to be the fire dragon because all the other dragons you have to hack for. NO. You don't have to hack for it, you can BREED it, the rarest is leap year or rainbow dragon because leap year comes after 4 years or so, then rainbow is rarest of ALL. Breed Mud And Blazing AFTER few tries and it WILL work, only for rainbow dragon. DONT LISTEN TO HACKERS, THEY BREAK YOUR GAME YOU MIGHT RESTART YOUR GAME ALL OVER! Try looking at Google because it's true nearly ALL the time.sometimes panlong dragon for mud blazing...
There are many types of rare dragons. An example would be the lunar eclipse dragon. The most common way of breeding this dragon would be a snow dragon with a mountain dragon.
You don't breed a Kairos Dragon in DragonVale. You have to get parts to complete it.
Yes it is, but the rarest is the RAINBOW DRAGON!!
you breed a ice dragon with a mine dragon
You have to breed a plant and a fire dragon.
As of July 2012, there has not been a star dragon in DragonVale.
You have to breed a sun and moon dragon together
You have to breed a metal and a water dragon together.
You have to breed a plasma dragon with a salamander dragon.
Breed the earth dragon with the fire dragon.
To get a Smoke Dragon, breed a fire and air dragon together.
There is no "marsh" dragon in dragonvale but if you are referring to the moss dragon the best way to get it is earth and plant, although you also have a chance to breed the tree dragon.
Earth Dragon and Cold Dragon