in island cave idiot
you need the the mystic ticket and then you go catch him at lv.70
you catch one
no you can, you most catch it in Pokemon emerald
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.
There is no possible way to catch Regice in Black or White, unless you use PokeTransfer or Dream World.
you need a action replay
you have to trade from diamond or pearl
No, it's not available to catch in Emerald. You'll have to trade one from FireRed/LeafGreen.
You can catch a Regice at Island Cave (Route 105)
you must catch regice,regirock, and registeel
the only way you can get regice in heart gold is by trading from Pokemon platinum,diamond and pearl
trade it i traded a charmander for one once