In this question http://pokemondb.net/pokebase/648/how-do-you-get-into-the-snowpoint-temple the answer by (Mewthree) says that you need to get regice,regirock,registeel from R/S/E and I don't have any of those games ,so is there another way I could get those in pokemon-diamond or is there any other way I could bring life to regigigas ?
Well, except using Pal Park, you may trade. Otherwise, no.
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