Changing Deoxys And Giratina's Forms:

If you want to change Giratina's forms be sure to have a Griseous Orb. Give Giratina Griseous Orb and a swarm of darkness will surround it and also you'll hear his cry. If you want to change Deoxys forms go to Nacrene City Museum. Once your there make sure Deoxys is in your party. Enter the museum; look at the meteorite and push A. It should say “Deoxys is reacting to the meteorite”. Select Yes when it says “Let Deoxys get near the meteorite” and there you go. Now you've got Giratina's other form and Deoxys other form. Warning if your Giratina is in Origin Form it won't work just a heads up.