Nottagen is the northeastern pedestal in the red pillar at the Shrine of Mysteries. Once you get into the new area, you can see an area that you can enter prior to getting to the main town. This is the Hill Near Nottagen and the only thing you'll find there is a Yellow Fragment on the ground. Once you get this, exit and move on over to the town of Nottagen. At the entrance, you will be stopped by two Babygoyles, triggering a fight. They're not very hard, hitting physically for about 20-25 damage and also being able to inflict sleep on your characters.
After taking them out, you'll be able to explore the town. Enter the southeastern house to find a Medicinal Herb in one of the pots, then go into the inn to find a Pointy Hat in one of the cupboards. You should now notice that monsters are living in the town with the humans, although they are there because they are forcefully living there. Anyway, go into the small house next to the weapon shop to find a Hairband in the drawer, then enter the weapon shop from the rear door. Talk to the forky pig blocking the doorway to get into a fight. Defeat it and open the two chests (requires Thief's Key) for an Iron Mask and Iron Axe .
There's a monster running a shop upstairs, although it isn't selling anything but trash. The only other building that's in the town is the big one in the north, but the entrance is being blocked by a Rockbomb. So, go behind that building and to the northwest corner to find a well, entering it to find a priest who can save your game, as well as a Seed of Resilience and Holy Water in the cupboards. Talk to the female NPC down here and when you return to the surface, you will find that the Rockbomb is no longer in front of the door.
If you're still hurt, make sure you rest up at the inn before heading inside the big house. Inside, talk to the old man downstairs and he'll reveal that he's actually a forky pig, attacking you. Defeat it and break the pots for a Mini Medal (#57) , then go upstairs to see a big monster sitting in the bath tub. Talk with it to initiate a boss fight.
BOSS - Moostapha
Boy, does this thing hit hard and could possibly one-hit KO some of your less than health-endowed characters. This boss is purely physical and as such, you will want to apply Buff (or Kabuff, should you have it) to all of your characters. His normal attack does around 60+ damage, while he has a desperation attack that can deal close to 100 damage or more. Moostapha can also stomp a single character for about the same damage as his normal attack, and can save his strength for a stronger attack. Since all of his attacks only hit one character, you shouldn't have any trouble, as long as you heal accordingly and increase their defense.
With the big moose-thing finished, go over to the drawer the one monster was guarding to pick up the Sulkk Key. As you walk out of the building, the owner will barge in and when you do get outside, you'll hear a large roar. Heal up, feel free to save and set off for the tower in the west. Before you enter, though, go on the western side of the tower on the overworld to find a chest that contains a Bottlenose Buckler .