Broken Magic (Percy Jackson, Harry Potter, and Gravity Falls crossover)

Getting ready for a year a Goode high school Percy and Annabeth get attacked by a monster.(That's no surprise!) Quickly they realize that mortals could see everything that just happened. The Mist is weak!

The Wizarding world is in denial about Lord Voldemort's return. Working secretly under the Ministry's noes, The Order of the Phoenix plots to take down Voldemort. Soon they discover that the magic has been weaker and a new prophecy has been prophesied.

Solving mysteries and hunting down monsters, Dipper and Mabel pines are having a wonderful time in their beloved Gravity Falls. But they are confronted by three strangers and plunged into another journey of weirdness.

Building new friendships along the way, the demigods, Wizards, and pines family discover the cause of the strange happenings of the Mist and magic.