Developer Page: Psyworks
(dev id no. 9 - prev next)
This one's mysterious. I don't know if they exist anymore, or if they ever really existed, or if they ever developed anything other than Sengoku vs Gendai. Their website returns a 403. All I can find is this job advert from 2003. Truly an enigma. One thing of note is that the company's name is officially written in Japanese as 彩WORKS, using the same "sai" kanji as Psikyo - could be an homage, could be a coincidence, could be something more.
Official Site: http://www.psyworks.jp
Simple 2000 Ultimate Series
Sengoku vs Gendai (Deadly Strike)