Annet has defeated Aisha, but Kirke begs her to stop. Earnest tells her that she'll end up killing her if this goes on. Zigfried claps and says Annet was amazing. Earnest says that they've won the game, and Annet begs Zigfried to show them how to turn the Princess back to normal. Zigfried agrees but politely asks for the idol. Earnest asks why, and Zigfried says idol has been worshipped by people since ancient times. The same can be said about the jewel in this pendant, but they you won't find it in any texts. Zigfried has been erasing any mention of it for a long time now.
Zigfried says he may look like a normal man to them, but he has lived for a very long time, longer than they can imagine or comprehend. Earnest asks exactly who the hell he is, but he just says he's same Zigfried you all know well. He then talks about the idol. It has the power to rejuvenate living cells, and let one stay eternally young. However, as they may guess from the twin faces of the idol, it also contains the opposite power -to destroy all life.
He then tosses the pendant to Earnest and tells them to put the gem into the statue's forehead. He also says, 'before he forgets', that as a condition for it to work, they need a human's "love" -not pity, not compassion, but true love. He laughs and says he doesn't think any of them possess such a thing. But Kirke then steps up.
Kirke places the idol onto Aisha, and it begins to pulsate with a bright light. As everyone watches, Zigfried is surprised the idol still has this much power, and that a human can draw so much from it. The light fades and the monster Aisha is no more -she has changed back to her usual self again.
Princess Aisha wakes up and is glade to see Kirke. Kirke is also glad she's alright and hugs her, but then Zigfried says he'll be taking this back now, and reclaims the idol. But Earnest says he won't be getting it, and quickly uses his whip to snatch the idol back away from him.
However Zigfried takes out his gun and shoots Earnest twice, causing him to fall over. The idol crashes into the ground and shatters into pieces. Zigfried thinks that was careless of him.
Annet rushes over to help Earnest, who is still alive, but she suddenly bounces back. She's been trapped with Zigfried, who tells her that as long as this barrier is in place, she can't reach him. She tells him to please let her pass, but he says she doesn't need his permission. Why not try using her own powers to break out? Annet asks how, and he tells her...
"...by simply defeating me!" Zigfried transforms into his own true form.
The final battle begins, against "Dark God Nyarlathotep". Nyarlathotep is a bit of a pain to fight. The actual main boss only has one attack. He can fire a string of fast projectiles, but these don't do much damage. But what does do damage are the two dog head things. These will knock you down on contact, and they'll either stay close to the boss, or slowly move in towards you before retreating. This fight is about patience and luck. Wait for the heads to move away from you, and then run in and do a cyclone blade. Hopefully you'll hit the boss without taking any damage yourself.
This boss is like the level 7 boss in the way that it can only move left and right, it'll never move up or down. However this means you need to be on a certain line to be able to hit it at all, and unlike the level 7 boss, it isn't clear here where that line is, so you'll just have to keep using cyclone blades until you manage to hit it. Annet's normal combo won't work on this boss at all, and her jump kick is difficult to hit him with, so the cyclone blade is the only effective attack you can use.
NOTES
During the boss fight, the health bar icon for the boss looks nothing like the actual boss you are fighting:
However, when you defeat this boss, two odd things happen -the health bar icon changes, but the defeated boss sprite also changes:
Basically, the health bar icon changes to the armored version of the boss, which you actually get to fight. The defeated boss sprite changes to what it looks like under the armor, which is shown in its first health bar icon, but you never get to fight this. This makes me think that Wolf Team might have intended for the final boss to have two forms, as it seems very weird for them to go to the trouble of making that separate sprite only to have it appear on screen for less than 3 seconds in the game. And they clearly screwed up with the health bar icons -they got them the wrong way round!