Harry Potter and the Order of the Phoenix is a licensed Game Boy Advance game that is based on the book and movie of the same name. It generally follows the plot of the movie and sticks to the exploration and minigame elements that were present in previous Harry Potter games.
Cephla decides to skip everything involving Dumbledore's Army and Dolores Umbridge by corrupting the save data so that Harry Potter and gang go directly to the Department of Mysteries and defeat all the Death Eaters there instead, ending the game early.