all these are hacks
Shiny Dialga 6IV, Adamant
Shiny Mew 6IV, Sassy nature
Shiny Giratina 6IV, Lonely nature
Shiny Deoxys 6IV, Sassy nature
Shiny Darkrai 6IV, Serious nature
Shiny Lugia 6IV, Docile nature
there is no perfect iv spread for gen 3. gen 4 only 4 natures can have perfect ivs and serious,docile,lonely and adamant aren't any of them