Pokémon Adventures, Vol. 27 by Hidenori Kusaka

When a mysterious armored villain in search of the Wish Pokémon Jirachi attacks Nolan, Emerald is the prime suspect! Jirachi grants wishes, but only awakens every one thousand years for seven days. How can Emerald and the Frontier Brains prevent Jirachi's power from falling into the wrong hands?!