You have a Pokemon hold them and then clone the Pokemon. (Put the Pokemon in the PokeWalker and turn the DS off before it saves)
Cant you can only on Pokemon heartgold search for how do you clone items in Pokemon heartgold and my answer will be there
You make them breed with Ditto.
You need to have a Pokemon hold the item then trade the Pokemon.
its all in the timing
Use items.
The PokeWalker allows you to walk with a select Pokemon from your copy of HeartGold and if you walk enough, you can capture extremely rare Pokemon (though not legendary).
An ability can do that also some items
If you mean clone then your gunna need a AR
You cannot go underwater in HeartGold. You could go underwater in Sapphire, Emerald, and Ruby, but not in HeartGold. Items are not underwater in HeartGold, either.
To get hippopotas in heartgold and soulsilver you need to go to safari zone and use special items.
Its not suposed to be. you just get items.
Go to Game Stop, Target or Wal-Mart.