So i noticed the game gets almost impossible to complete, after you purchase a good body armor and a new sword. There are twice as many monsters in every battle and you fight 2 at a time. For me that was quite impossible to complete since its really hard to dodge 2 of those monsters that try to run you down - dont remember the name. Also fighting to spearmen at once is almost impossible.
TLDR: Just kill of every monsters and knights before purchasing any of the good stuff