you need to go get the adament lustrous orb on you way to cornet and go to clelestic town.talk with elder go to spear pillar and boom there
Catch palkia first.
For diagla and palkia you need to go into the cave for where you got the orb for giratina (if you don't know what cave I'll send you a link on youtube to get the orbs) after you find the orbs you go to spear pillar where you got giratina then when you enter you would see a blue and pink figure. You click the figure to fight diagla and you click the pink figure for palkia. Make sure you save your game before you catch them. I suggest using giratina and use dragon claw then use an ultra ball (that how i caught mine using one ultra ball) Good luck!
no u cannot if u fainted them
You have to make it to the spear pillar to do that you have to beat team galactic a lot of times.
find palkia come back
After the Giritina event, climb up Mount Coronet and go into the room in through the entrance that was once blocked by a Team Galactic Grunt. In there you'll find the Adamant Orb and the Lustrious Orb. Take them up to the Spear Piller and examine the Blue and Pink orbs that appear. The blue one will make Dialga appear and the pink will make Palkia appear.
Use it.
After deafeating dialga in platinum exit the door and come back you will see a pink portal click on it and you will find palkia lv 70 make sure you save before you do it
no you need to have the three regies in your party to make regigigas appear
It is impossible to get Palkia to have an egg, because Palkia is genderless and cannot be bred.
Nintendo random event.
Regigigas sky form is not real