Yes, I noticed that you can buy and sell as much bread as you want, and it is very expensive to sell. So I sold enough to buy the armor and as many potions as possible (x100 each). there I was able to defeat Arthur at level 2 but it took me almost an hour. In any case thank you for your answer :)
Announcement: The Chronicles of Lancelot Demo Release and Releasing Process Update ヽ༼ຈل͜ຈ༽ノ » Comments
We cut off the Arthur flow in the demo so I set Arthus HP to really high so the re-popup wont happen (yes he will in the demo if you beat him since his quest flow was cut), so you have my respect Solymas and Djyemee xD The guys under the bridge always gives you a new necklace if you sold the old one.