Hoping to make your life's design a bit more dynamic!

Pleased to be fiddling my way through them! Unfortunately I'm not going through the game with the intent of documenting things, but just getting through it should be enough for me to give advice on it eventually... I could see a reasonably strong English following for I Wanna Be The Hermit purely on the basis of its difficulty, so with enough word getting out that guide might not be far off.

I am at the part where I got the three mirrors and have to go through some mountain pass. I seemed to be under-leveled, main character level 26 because I had a hard time beating the boss (who said he hates girls or something). After coming out the other side, my goodness the enemies are strong! I figure I need to get at least 5 levels!

That Nim game though, ugh!

I thought that the boss at the mountain pass was a woman who said that she hated men, but strangely changes her mind after being beaten by the hero and his party. Well regardless, there's lots of guides on Youtube for beating "Nim" type counting games. Here's three good ones that I've found after a quick search:

https://www.youtube.com/watch?v=9NePwJlxkk8
https://www.youtube.com/watch?v=mR6mVm4SuRw
https://www.youtube.com/watch?v=dUXW3Kh_kxo

There's various helpful guides on the internet for solving the other types of puzzles as well, but nothing game specific in the form of a walkthrough or FAQ yet. You just have to take some time to think about each one and also experiment via trial and error. The good thing is that there's no time limit nor consequences for failing any of the puzzles, so you may retry as many times as you need to until you succeed.

Edit: I forgot to mention that all items in this game are sellable. Any story related items can't be sold, so there's nothing game breaking. On a few occasions, you will find armor and weapons that you can't equip yet, but can sell for a high price. Latter on, you will have more than enough money to repurchase them when your level is high enough. So you may sell whatever you like now if you need the money. I remember selling a "Steel Sword" I believe early on that you find in some town between two mansions or something along those lines (an NPC gives you a hint about searching somewhere at the top center of town between two rich houses).

This is exactly the type of thing that's good to know from someone who's finished. I have a lighter conscience about resources in this game now!

In the meantime, a few more prices, all maximum this time:
Crystal: 1050 G
Dagger: 7 G
Iron Sword: 3150 G

P.S. The horse thing was brilliant!