Volt's Draconic Ascension

Channeling the latent magic stemming from the draconic meddling of the sorcerer's bloodline, this spell allows caster to permanently become a dragon of the chosen variety, with the ability to polymorph into original humanoid form. The age of dragon is determined by amount of gold used for material in casting of spell. The spell takes a minimum of eight hours to cast to become the first tier  listed. For every desired tier above base,  it requires and additional eight hours. 

0-1,000 Gold: Egg of chosen dragon
1001-4.999: Wyrmling of chosen dragon
5,000-9,999 Gold: Young Adult of chosen dragon
10,000+: Adult of Chosen Dragon

The only way that this can be reversed is through either an equal level casting of remove curse or the wish spell.