Inspired slightly by this: http://finalfantasy.wikia.com/wiki/Elder_Wyrm_(Final_Fantasy_XII)
The first form would be Dragon (or Dragon/Ghost), and it would be a dead/sick looking young dragon, perhaps made of bone or just bony
One evolution (perhaps through sun/leaf/dawn stone) would have grass/moss/other plant life blossoming off of the skeleton/body, and it would be Dragon/Grass (sort of a peaceful death/moving on, if you want to look at it that way, with the opportunity for new life)
The other evolution option (perhaps through a dusk stone) would be poisonous, sort of rotten (but not too bad of course, this is pokemon, maybe just dead/purple plants), and would be Dragon/Poison (analogous to the first, it would be like an angry/bitter death)
Thoughts? Sorry that it was poorly written, it was hard to exactly articulate my thoughts. --- Currently awaiting: Lunar Knights 2, AC:NL, Pikmin 3, XY, WW HD, LR:FFXIII, X, LoZ U, FFVXIII Skarmory would slap the hell outta you
Sun stone- green, Grows more scales and looks less bony. Has some flowers on it, learns some healing moves (aromatherapy, stuff like that) Moon stone- gray, bonier, pretty much a skeleton, exhales purple smoke, learns some status inflicting moves --- Rocket Professor ~ R ~ Support Elesa! Real Arceus. Third Version M 2/26/13 Official ANBU of the Pokemon boards.
I tend not to take those too seriously. There are some creepy ones tho. (Beautifly, right?)
If you want, you don't have to take mine "too seriously" either, just as inspiration --- Currently awaiting: Lunar Knights 2, AC:NL, Pikmin 3, XY, WW HD, LR:FFXIII, X, LoZ U, FFVXIII Skarmory would slap the hell outta you