The sprite world is a dungeon dropped by sprite children which can be found with Sprite Gods inside the Godlands. Sprite worlds are pretty common and are the source of dexterity potions and for some UT loot.
As it is pretty easy to solo, it can be hard for newer people. The sprites themselves aren't a problem but a sprite god will be as it pops up randomly and can easily kill people with low defences. Most of the dungeon can be pretty easily skipped by the cloak of the planewalker witch is a drop of the boss Limon the Sprite God . Limon can be pretty hard to kill if you have low speed as in her first phase, she will run to you and try to kill you with a "shotgun" kind of attack.