When you get down in the maze, like sam sam sam sam said, you go left after beating the grunt. Continue going left until you reach a flight of stairs. The stairs go up about 5-6 floors. At the top there is an item on the floor. It is e-quake. Pick it up then jump off the little ledge you where on. Then step out into the desert resort.
Note- the maze section is only availible after the league has been beaten for the first time. To get to the maze, go down like the time you had to find gehetsis, then go to the very right of the room, & there is a door, the entrance to the maze.
You can also find volcarona in there.
Hope this helps