you cant you have to get it on emerald/sapphire/ruby then migrate it to pal park
You can only catch it in Ruby, Sapphire or Emerald and migrate it over. If you get an event Regigigas on Pokemon Platinum you can catch Regice there.
you need REGIROCK, REGICE, AND REGISTEEL.
you cannot catch any regis in platinum you have to migrate them or trade for them but if you get regirock, regice, and registeel on platinum then you will be able to catch regigagas at level1 in the snow temple
the only way you can get regice in heart gold is by trading from Pokemon platinum,diamond and pearl
he is usually lev.30 so at the start use a quick ball and you will probably catch him
In one of the empty caves just check everywhere
To get regice, you need to either get it from ruby/sappire/emerald, or you can catch it if you have gotten the level 100 regigigas from the event before the release of platinum.
yes but only through the special Nintendo event
No; you cannot catch the three Regis in Platinum, UNLESS you have obtained a special Regigigas through some special events.
Yes, you do need the National Dex if you want to get into the Regirock, Regice and Registeel caves in Pokémon Platinum.
You catch regice
Yes, that is the only way.