How to evolve Onix into Steelix in Pokemon Brilliant Diamond Shining Pearl

Alec Mullins
How to evolve Onix into Steelix in Pokemon Brilliant Diamond and Shining Pearl

Onix is an iconic piece of the Pokedex, but evolving one isn’t as simple as reaching the right level. There are a few more steps you’ll need to take to get the Steelix of your dreams in Brilliant Diamond and Shining Pearl. 

Both Onix and Steelix are memorable in design and in strength, but making the former turn into the latter is a bit of a headache.

While Onix is one of a few pokemon that require a trade to evolve, the process is additionally convoluted by the inclusion of the elusive Metal Coat item.

Where to find Onix in Pokemon Brilliant Diamond and Shining Pearl

As a non-exclusive Pokemon, Onix can be caught in both versions of the game. The most likely locations to run into one are said to be Big Bluff Cavern, Iron Island, and the Orebugh Mine. 

Finding a Metal Coat in Brilliant Diamond and Shining Pearl

Byron on Iron Island holds the Metal Coat that you'll need to evolve Onix into Steelix
Byron has a Metal Coat for you in Riley’s House at Iron Island.

The second step in the process requires trainers to find the extremely rare Metal Coat item.

There are two ways to go about this:

  1. Unlock the National Pokedex. This requires you to see every Pokemon in the Sinnoh region as well as complete the Pokemon league. After meeting both of the requirements, players can up the Metal Coat from Riley’s House on Iron Island.
  2. Make a visit to the Grand Underground and use Thief to take it from either a Bronzor, Magnemite, or Beldum that is holding one. Alternatively, you could capture the target and take it from them in the menu.
  3. Make the Onix that you intend to evolve hold the item in preparation for their evolution

How to evolve Onix into Steelix

Another semi-unique aspect of Onix’s evolution is the need for a trade. This means that the player who sends the Onix will not get to see the evolution or keep the Pokemon, but you can bypass this by trading your Onix for another one that is also holding the Metal Coat item.

All players will need to have beaten the game’s first gym leader Roark in order to access the Local or Global rooms that are necessary to trade.

If you’ve met all of the benchmarks, here’s what you’ll need to do:

  1. Load up Pokemon Brilliant Diamond or Shining Pearl.
  2. Visit any Pokemon Center and enter the Local or Global Room
  3. Setup a room to trade your Onix
  4. Complete the swap and watch the Onix you receive become the Steelix of your dreams.

That’s all you need to know to evolve Onix into Steelix! For more guides, check out this list below…

How to get Eevee | How to get Leafeon | How to get Glaceon | How to get Umbreon & Espeon | Where to catch Spiritomb | How to get Riolu & Lucario | Where to find Gible & Garchomp | How to unlock the Bike | All trade evolutions