u cant it can only be bought.
i put a blazing and a lighting dragon together and got a sonic
To get sonic wait dont buy it but just breed a lighting dragon and a flying dragon to breed a flying dragon you need to breed water and fire so remember dont buy it
You don't breed a Kairos Dragon in DragonVale. You have to get parts to complete it.
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.