The Fortress dungeon is one annoying crawl. That took a while and certainly it has some annoying monsters inhabiting that place and some puzzles are a little tricky to solve but it's doable. there are also plenty of warp circles that send you around to other places in the map plus pit traps that drop you down to a lower level or cause you damage. Lookout for treasure chests that have arrow traps and ones that are fake and attack you !!!!!
Some of these maps have ice when stepped on will send you sliding and you could fall into a hole that sends you back to a previous map..
The trickiest levels in the fortress are probably Fortress 2 where once you activate a certain switch you will unleash some monsters, one of these looks like a pixel meshed egg-like monster called Erase Eye which erases your map discovery. So you will need to kill them quick. They also raise your magic defense considerably if you let them attack you from afar.
Might want to play around with those wall switches. Also this dungeon has lots of hidden paths. aka magic walls along with traps that hurt a lot!
Fortress 5, 6 and 7 are inter-linked so there will be some warp circles that send you back and forth, floor pits some of these will hurt you and others will allow you to fall to areas below and hopefully parts of the map where you couldn't reach before.
The last few levels If your magic defence is weak you can block the projectile attacks and it should boost your magic resistance. Hide and rest to regen both your hp and magic bar and repeat.
It's here in this final dungeon you might have to help ドーラ ドロン / Dora Delon's life. I didn't try to kill her here so I don't know if you can or whether this affects the outcome of the ending. Well her original intent was to kill you.....
Something awaits Ares but if you have high magic def it should be quite easy to take down.
Boss Belzahydra.
Don't matter which head to take down first just kill it anyhow. After that you can unlock the other chests and also pick up the planet Buster sword.
Final boss time...
It's probably been undisturbed and lying around for more than a 1000 years but now it's time to meet a former king.. Boss Berebus
These two magical machines scroll left and right. They shoot magic laser beams front and both sides. Just hack away and heal/ use rings of protection. One by one they fall so use the purple warps to advance forward.
Then you will eventually reach Berebus himself..
Avoid the green warp circle and while his two arms fire magical laser beams down at you just hack away.
Berebus was once a king. And the city he lived in Vittoria was protected by a huge dragon that was perched ontop of a huge tower. Fortunately for the people surrounding this tower the dragon brought protection and the city flourished and trade was booming. After being presented with an ancient tome the king sought the power of the dragon and what possibly could be hidden at the top of the tower and decided to take down the dragon's and possess whatever treasures hidden within for his own. The dragon gave in and it's power transferred to the king. Unfortunately for him he couldn't contain the amount of power flowing into him and because he was filled with selfish deeds he began to transform into a monster and the city sank and was never heard of again for a thousand years.....