Ever since finding out that Spellcaster for the Sega Master System and Mystic Defender for the Sega Genesis were part of the same series in Japan, Kujaku Ou, I've been trying to track down as much info on the series as possible. I do know that all of the games were based on the Kujaku Ou anime series, which has been released in the U.S. (although I have yet to see them myself).
To date, I haven't found a lot of info on the different games in the series, as pictures and other info on them seems to be on the almost nonexistent side. Since the only Kujaku Ou games that made it out of Japan were altered, and the anime series was only released in English just recently, I'm really not surprised about the lack of info. However, what I have found I'm presenting to you here. Below is all of the info and screenshots I've gathered from various sources.
Here's a side-by-side comparison between Kujaku Ou and Spellcaster. Besides the name change for the U.S. release, the in-game sprites were altered, as you can see from the pics below. Unfortunately, I don't know of a way to change Spellcaster over to Kujaku Ou like I can change Mystic Defender to Kujaku Ou 2...
Kujaku Ou on the left, Spellcaster on the right
Here are the covers to both Kujaku Ou and Spellcaster. As usual, the Japanese cover looks so much better.
Kujaku Ou back cover
Here's a side-by-side comparison between Kujaku Ou 2: Geneishiro and Mystic Defender. This should give you an idea of how the game sprites were changed when Sega of America got their hands on it (not that these particular screens really show all that many of the changes), just like when they changed Kujaku Ou to Spellcaster.
Kujaku Ou 2 on the left, Mystic Defender on the right
Thanks to geelw, I now have scans of the box and manual for Kujaku Ou 2. Check it out... they do show Alexandra nude, just like she is in the game - for more on this, check out the article Tonight in Mystic Defender: LIVE NUDE GIRLS!
Manual Pages #1
Manual Pages #2
As a bonus, here's the cover of Mystic Defender. It's definitely not an improvement over Kujaku Ou 2's cover.
Armed with a cursed sword, Nobunaga Oda - the Sixth King of Evil - is about to be reincarnated. Now, Kujaku and his allies must defeat the warlord before he can revive the unholy power hidden within the crumbling walls of Azuchi Castle. But if Kujaku should fail, the world will collapse into a fiery pit 1,000 miles deeper than hell...
This picture from the end of the anime looks almost exactly like the shot at the end of the game, too. Check out the comparison.
System Shock, a website that seems to specialize in ROM patches enabling you to play the original Japanese version of an altered U.S. game, did a feature on Kujaku Ou 2 in issue #5. The article is short, but interesting, and features a small one panel "comic" that I've taken and added here. I also cribbed the two flaming character graphics at the top of this page from System Shock as well. ^_^