#Angel

Angels are badass. They are always appearing to cause trouble and no one knows why. Angels don't have to be emissaries of God. They are alternatively represented as Half-bird/half-human things or occasionally as thinly-disguised demons.

http://media.animevice.com/uploads/3/37524/677068-safer_sephiroth.jpg

##Classic fantasy based, preferably Western culture originating. Definately, originates from one of my favorite fantasy books of all. Angels originate from Western culture but they have been used as villains to great effect mostly in Japanese games.

##They can't be a standard biped race, humans and elves are so last millennium. Comes literally from the last millennium.

##Not a dragon or a dragon clone. Check

##Living. Breathing About as mortal as an elf.

http://bayonetta.wikia.com/wiki/Jubileus,_The_Creator

##Lone being Perfect for the lone being, Angels are lonely in nature, being all up on their high horse.

##Could control an entire realm/kingdom on their own by sheer force of will and personal power Angels can be super-powerful and have been known to mess stuff up.

Overall, an Angel makes an interesting enemy for your campaign as diplomacy with them is very different. He would probably come from an angle of "purifying" the land of "evil" and so your characters would need to employ unique tactics to reason with him/her.

Additionally, this allows you to explore themes like religion, ethics and the afterlife.

http://static.comicvine.com/uploads/original/7/72615/2418856-kefka___final_form_by_sarifus.png

Angel

Angels are badass. They are always appearing to cause trouble and no one knows why. Angels don't have to be emissaries of God. They are alternatively represented as Half-bird/half-human things or occasionally as thinly-disguised demons.

http://media.animevice.com/uploads/3/37524/677068-safer_sephiroth.jpg

Classic fantasy based, preferably Western culture originating.

Definately, originates from one of my favorite fantasy books of all. Angels originate from Western culture but they have been used as villains to great effect mostly in Japanese games.

They can't be a standard biped race, humans and elves are so last millennium.

Comes literally from the last millennium.

Not a dragon or a dragon clone.

Check

Living. Breathing

About as mortal as an elf.

http://bayonetta.wikia.com/wiki/Jubileus,_The_Creator

Lone being

Perfect for the lone being, Angels are lonely in nature, being all up on their high horse.

Could control an entire realm/kingdom on their own by sheer force of will and personal power

Angels can be super-powerful and have been known to mess stuff up.

Overall, an Angel makes an interesting enemy for your campaign as diplomacy with them is very different. He would probably come from an angle of "purifying" the land of "evil" and so your characters would need to employ unique tactics to reason with him/her.

Additionally, this allows you to explore themes like religion, ethics and the afterlife.

http://static.comicvine.com/uploads/original/7/72615/2418856-kefka___final_form_by_sarifus.png