The Moonstone Shard drops off Fairy Queen Timiniel in the Enchanted Valley. It is used when crafting a Royal Demon Tattoo.
Finding Fairy Queen Timiniel
Once in are you at Hunters' Village, you will take the Northwestern exit (up the wooden ramp) and follow the road to the Enchanted Valley.
There are many paths to find Fairy Queen Timiniel, here is a map that shows you two main ways to get to her. The main path is shown in red, while an alternative Northern route is shown in blue. Her location on the map is found inside the green circle. She has a 2 hour respawn time.
Fairy Queen Timiniel is strong like a raid boss, you will need a decent size team to take her down.
Fairy Queen Timiniel and her eight minions have very high speed, attack speed.
They are weak to wind attacks, and very weak to bow attacks.
Strong resist to dark, earth, debuffs and high magical defence.
Evasion is very high so it is a good idea to buff for accuracy.
This boss is designed for experienced and skilled players.
So make sure you have decent size group with both a confident tank and disciplined observant healer.
Good luck and have fun!