You can get it at the snowpoint city temple at the bottom of the temple.
in the ice temple in snowpoint sity
You Can't... that's in Pokemon diamond/pearl/platinum
First beat the game then get the national dex and then you can go in!
You need to have all 3 regis and go to the snowpoint temple.
Regigigas in snowpoint temple
You have to get regice, registeel, and regirock. Then go to snowpoint temple in Snowpoint City and go to the bottom, bring the Pokemons.
You can find Regigigas in Snowpoint Temple in Pokemon Diamond, you will need to bring Regice, Registeel and Regirock for Regigigas to waken.
First get the national dex then beat th elite4
You'll be able to go inside Snowpoint Temple. Regigigas will be in there.
You can catch on at the Snowpoint Temple. However, you must have the 3 Regis in your party.
You beat the league. If you mean the snowpoint temple all you have to do is beat the Pokemon league but if you want regigigas you need regirock, regice and registeel