No...
It increases your Pokemon's defense.
There is one at the end of Iron Island
You ride a boat there it's true
go to iron island. riley gives it to you at the entrance
There is no person or group called the iron guard in Pokémon Pearl version. However, there is a move called no guard.
You can't get to it on Diamond Version. Only on Platinum Version. It isn't on Diamond Version. Plus, you have to have a special Regigas from Mystery Gift that they don't distribute anymore. Owen
Some Pokemon will learn Iron Tail such as Rock, Ground, and Steel types, you can also find it in caves or on the ground in a item ball.
Pokemon ruby's version IS Pokemon ruby.
Pokemon Black Version & Pokemon White Version.
The only way to get the 3 Regis in Pokemon Platinum Version is if you have the Regigigas given away at Toys 'R' Us. Only that exact Regigigas will activate the other 3.\actually Registeel is in the Iron Ruins inside of Iron Island B3F.
No.
Pokemon Dark Cry version.