In Leaf Green and Fire Red, you can't. You must trade them over from Ruby, Sapphire or Emerald.
no it is not possible
You are not able to catch the regis in Diamond. You can catch them in the Game Boy Advance version of Pokemon Emerald.
nothing. you catch them. what more can you ask then the regis'? don't be selfish! and you cant catch regigigas.
no.
For Pokemon ruby you can catch the three regis, rayquaza, groudon, and latios/latias. In sapphire you can catch the three regis, rayquaza, kyogre, and latios/latias. However, in emerald you can catch kyogre, groudon, rayquaza, the three regis, and latios/latias.
You need relicanth and wailord to catch the regis in sapphire/ruby/emerald. You cannot catch the three regis in platinum unless you have the event Regigigas (this event has now ended). If you have the special regigigas in your party, three new caves will open up in Sinnoh and you will be able to catch the three regis.
Be more specific. What game?
Yes.
Yes.
A Masterball.
no you can catch them in any order trust me ive tried.
You can not catch them in a luxury ball, sorry dude.