To obtain this achievement, you need to stay and sleep inside an Inn/Tavern aside from the Mestrokia Village's Inn. The nearest one from the start is the Furrensit Town Inn shown below.

It's the same with the Inn achievement, you should go visit the clinic in other towns aside from the Mestrokia Village's clinic. The nearest clinic from the start is in Oblivia. The church in Furrensit Town does not offer such a service. And don't worry about expenses because the service is free.

To get this achievement, from Oblivia go east. Then talk to the horse keeper. He'll bring you to the Mystic Mountains for a service fee of 25f.

This is one of the trickiest among the 5 achievements. Face the well located on Mestrokia Village and interact with it. A dialogue box will appear and ask you if you want to go down. Choose "No" and you'll get the achievement.

This can be done in a lot of ways but the easiest would be: From Oblivia, enter the Ancient Forest. Keep going south until you reach the enormous map area of the Ancient Forest. After that, go west. You should end on a map with a waterfall, interact with the sparkling thing on the left side of the waterfall and you'll get a strange key.