You have to transfer them over from Pokemon Ruby, Saphire, or Emerald.
you must get the three Pokemon reggirock reggisteel and reggice to get them you must have sapphire, ruby or emerald i don t know how you get them on there sorry but i have looked it up before
reggisteel is in route 220 reggirock arrives in your secrent base when your base is in a rock and reggice is in seafloor island this was teatsed and it works 100% im really sherr because i have all the reggis (hint when reggi rock appears in your base hes black level 80!! its true man!!)
you get reggigas when you get reggirock, reggisteal, and reggice and go back to snow point temple to the reggigas statue and battle him
The legendarys? Well. The ones i know of are. Darkrai,Manaphy,Froslass,Dialga,Palkia,Giratina,Groudon,Kyogre,Mesprit,Azelf,Uxie...Ummm..Celbie<-I spelled that wrong lol sorry. Moltres,Zapdos,Articuno,Entie,Suicune,Raikou...hmmm...Cressilia...Ho-oh...Lugia...Latios...Latias...Thats like all i can think of oh wait! Reggigas,Reggirock,Reggice,Reggisteel, And i think i spelled those wrong to but yea :)
you are not allowed to unless you use GameShark.
you need wailord (route 139) in the front of your party and relicanth( underwater somewhere) at the end of your party
you get the level 100 regigigas in the event (pokemon.com) then you go to mt cornet and you find a ice cave somewhere in there inside the cave there will be button looking things you step on them and go to the statue P.S.the regigigas from the event must be with u all the time
you could find it in the snow point city in side the temple. but it sometimes says something and you could also find reggigigas inside along with reggice.
When you take all the reggis to the chaber in Diamond/pearl you get a chans to capture the legendary Pokemon "Regigigas". He is a much bigger reggi than the other, and he is Normal type.
If you mean "a body of rock, a body of ice, and a body of steel, when gathers the three Pokemon the king shall appear," you need a reggice, registeel, and a regirock. Migrate them from Pokemon sapphire, ruby, or emerald. But that's not wat ur talking about is it? u can get an icy rock at the Underground!!!!!
Regice can be found by going to petalburg city and going over toward the woods and surfing down after going as far left as possible when you run into an opening you go left and up till you reach a cave there is where it can be found but before the cave will open you must have already opened the doors by going to the under water cave in the fast currents with a relicanth and wailord.
First, go to dewford town (after you have defeated the poke league) and go to the top of the town (make sure you have a Pokemon that knows the move surf). Next go left then straight and keep going until you cant go anymore. then go straight up until you find a small island with trees, go to the left edge of the island and then go straight up and then keep surfing from their (when you see a spot where you can start surfing again). P.s the discribing isn't that good
First you need Dig, Surf, Strength, Fly, Rock Smash, and Dive. For pokemon, you need Wailord and Relicanth. Go to Pasifidilog town, bring dig, wailord, and relecanth. Surf till you find a dive spot, then go the white rock that has dots on it. then dive up. youl be in a cave, then use dig in front of the back wall with dots. then walk to the back wall with dots. put wailord last, relecanth first. press (a) there should be an earthquake. then go to dewford for regice. surf on route 105 till you find an island surrouned by rocks. go in. wait in front of the dot wall for 2 min then it opens for regice. mauville go to the bottom of the desert (near the fossil tower) go right 2x the down 2x then use strength. then catch regirock. fortree time! go to fortree, then down route 120 to the place with the fossil maniac. then go in to the middle of the cave and use fly. catch registeel.
You can get Regice by arranging a trade with someone else and you can also transfer Regice from a previous game via the Poké Transfer system. Additionally you can make Regice available in your game by having a player with Pokémon White 2 send you a copy of their Iceberg Berg once they've received it in their game.