I figured I would start a thread where we can discuss the extra boss fights from Disc 4. So far I know of:

1. Blue Dragon (norther part of the map)

2. Cave Worm (forgotten cave)

3. Yellow Knight (break all 8 seals)

4. Persona (old sorceress's mansion)

5. Sacred Beast (by Numara)

6. Keroron King (keroron forest)

I have yet to find any of these bad boys. I defeated the 5 beasts that attack Numara, which I thought was the sacred beast, but no achievement unlocked so I guess that wasn't it. Has anyone found, or does anyone know where these bosses are located?

Please share any info you have on where they are, how to beat them, and any other bosses that are out there!

I just beat Persona.... what a ***!

It has 2 faces; one absorbs magic and one absorbs physical attacks. Problem is, when you set up to do a spell, it knows and is fast enough to switch before a single spell can go off. Then you end up healing it...

The way I beat it was to have everyone learn Consecutive Item from Sed, then stocked up on magic items. Once the face turned to the magic side, I had everyone chuck everything they could (became expensive!). That was faster timing then it's turn so I could get off hits, and was usually enough to get Persona to change faces. Then I had Kaim and Seth attack once, and everyone defend or heal. Then the face would change to magic. Repeat.

This was very hard as Persona's attacks are really hard and will also turn you into stone. I beat it with only Sed left, no items, and a single attack at 52 HP. I was on the edge of my seat!!!

i wonder if the blue dragon one looks anything like blue dragon shadow from "Blue Dragon"

how do i kill the cave worm i do like 1 dp and my magic only does 600dp i cant use items or anything any tips??

Also, there is the boss in the temple of enlightenment, the Anchient Spirit Magician Fu.

The sacred beast was so easy I was disappointed. Although you get a great item at the end. I still have the knight and fu left, but so far persona was the biggest pain. Generally speaking, they are fun sidequests with some good rewards.

If you open up your map when you're departing for anywhere with your ship (you'll need the white boa to get to most of the extra bosses) pretty much each of those shinning spots on it are bosses.

Not only do you need the Boa, but you need to make sure that you have every port unlocked as well.

Side note:  Make sure that your characters are well leveled up, esp Mack for Fu.  I had to start over as the first time I tried I was so under-leveled I didn't have a chance.