Chaos Sword
After going over the bridge out of town, turn left onto the beach and turn right at the shrubbery to find a path leading upwards. You will find a campsite, and a short intermission for your journal. Inside a trapped chest is the Chaos Sword. This is a powerful sword that poisons, but requires a 25 Strength to wield.
Extended ending
At the ending, if you have any character from the beginning of the game in your party (Abrecan, Brenna, Godric and/or Rheda), then the king will have an additional scene for each character. If you have any other character, then no additional scenes will be shown.
Free Battle Axe and Armor
When you talk to Brenna outside the castle and have an extra space in your party, tell her it is too dangerous. She will give you a free Battle Axe and Idem Scale.
Free Inferno Flask
In the town outside Gwernia castle, there is a house with a lean-to built on. Inside is a bag with an Inferno Flask, a powerful item for Godric, or anyone with Alchemy.
Shortcut to Erromon
Go to the abandoned Chaos camp where you get the sword and follow the trail north until you reach a path. Then take that path to Erromon.