The Black Orb — Gregory M. Tucker

It started with The Goblin Tree. A place where good and evil tumble and play through a world of fairies, magical charms, crystal caves, dragons, and amazing adventures, the magical world behind the Goblin Tree door is once again facing terrible peril.

A year after the Sibling of Magic--siblings Brylie Bell, Bailey, Branson, Lantz, and Abbey--defeated the evil Lady of Doom, she is at her schemes again. In her plot to destroy all that is beautiful and good, the Lady of Doom crafts a black orb with enough power to destroy both the magic world and the real one. This time, she enlists a crafty vampire to help her. But dealing with vampires is tricky, and to bring a vampire into the magical world of the Goblin Tree, the Lady of Doom must play a devious trick on the Sibling of Magic.

The second book of The Goblin Tree series takes the Siblings across the Valley of Filth, to the top of Styx Mountain, and into ponds filled with magic jokers.