The Powerful Two

Friends Jennifer and Skyler were both born with the powers of all the elements, but they did not know about these special and dangerous powers. When Pitch Black, The Booger- I mean, Boogieman, comes back, he tries to convince them to join him, in the destruction of the world. It's up to the guardians to stop him, and convince Skyler and Jen to help defeat him. But what happens, if after they defeat him, he comes back? What happens if they find their good friend Percy Jackson, during their mission?