NO FINAL FANTASY ALLOWED!

Who are the best antagonists from a Japanese roleplaying game or series? One of the things I loved so much about Xenogears was its cast of villains. Xenosaga was similarly great.

What other series have memorable and beloved bad guys?

(I am kinda looking to see if Wild ARMs has any cool baddies since I want to start that series)

Apparently some guy from Valkyrie Profile is really popular.