Plenty of Pokemon can evolve by reaching a certain level of experience. Others require the assistance of Evolutionary Stones. Rarer are the ones who need to be traded in order to evolve, like Haunter and Kadabra. But even within that relatively uncommon category, there exists a subset of species who need to be traded while holding the right item.
In Pokemon Brilliant Diamond & Shining Pearl, one such item is the Metal Coat. The Metal Coat is necessary to trigger the evolutions of Onix into Steelix and Scyther into Scizor. Steelix and Scizor both pack a punch in the main game and are even useful in competitive play, so many fans will want to get their hands on one or both as quickly as they can.
Finding the Metal Coat in Pokemon Brilliant Diamond & Shining Pearl
There are two ways to nab yourself a Metal Coat in Pokemon BDSP. The first involves locating one at a fixed location; the other can technically afford you an infinite number of Metal Coats, but it can take quite some time before you manage to find one.
Unfortunately, attaching a Metal Coat to either Onix or Scyther and trading them to trigger evolution consumes the item, prohibiting future use. Whatever it is that these two Pokemon are doing with it, it's clearly an act of premeditated violence.
For this reason, you will need to collect two Metal Coats if you want to evolve both Onix and Scyther. We'll start with the easier of the two.
Get a Metal Coat on Iron Island
There's a free Metal Coat just waiting for you if you return to Iron Island after you have obtained the National Dex. You won't get the National Dex without first becoming Sinnoh League Champion and seeing all 151 Pokemon native to the region, but the Metal Coat is just one of many reasons why the effort involved will pay off in spades.
Once you're back on Iron Island, head over to the house that's right outside the cave. There, you'll find Byron, and he'll happily hand over Pokemon Brilliant Diamond & Shining Pearl's only guaranteed Metal Coat.
Farm for Metal Coats in the Grand Underground
There's a whole lot of fun to be found in the Grand Underground. You can search for statues, for example — a time-consuming ordeal, but well worth it if your goal is to catch 'em all.
During your Grand Underground expeditions, you may very well encounter both Bronzor and Magnemite. These two species have a rare chance of carrying a Metal Coat when they're caught. This is your best bet if you need a second Metal Coat, and it's the only reliable way to gather a large number of them if for whatever reason you've decided your life's goal is to breed dozens of perfect Scythers or something.
Alternatively, you can teach TM46 Thief to one of your Pokemon and save some time by attempting to steal a Metal Coat from Bronzor and Magnemite instead. Honchkrow and Skuntank make great thieves, but the Sinnoh Dex is chock full of other candidates.
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