
In Pokémon HeartGold & SoulSilver, there are only 2 ways to get Charcoal.
The first charcoal you can get is in Azalea Town from the charcoal cutter. You’ll get it after rescuing his Farfetch’d in Ilex Forest. Another charcoal can be found later in the game in the Ruins of Alph, but only after catching Ho-Oh.
Charcoal is a held item that increases the damage of all Fire-type attacks by 20%. It can be obtained before challenging the Bug-type Gym in Azalea town.
If you’re struggling with the Gym, this item can give you quite the advantage if you have a Fire-type Pokémon on your team.
Method 1: Rescue the Farfetch’d

The first Charcoal is given to you after rescuing the Farfetch’d that belong to the charcoal cutters in Azalea town.
This quest can only be done after defeating Team Rocket and rescuing the Slowpoke from Slowpoke well.
Step 1: Exit Azalea town through the West exit. Upon trying to leave you will be confronted by your rival. After defeating him in a battle you can then enter Ilex Forest.

Step 2: After entering the forest, talk to the NPC standing near the entrance. He will tell you that the Farfetch’d have escaped and asks you to catch them for him.
To catch the Farfetch’d, you need to sneak up behind them or they will run away.

Step 3: To catch the first Farfetch’d, step on the first set of branches. This causes the Farfetch’d to look in your direction. Then walk around the trees, as shown below, to sneak up on the Farfetch’d.
Make sure not to step on the second set of branches or else the Farfetch’d will hear you, and you’ll need to restart the process.

Step 4: The second Farfetch’d is a little trickier to catch.
First, you’ll need to interact with it from the front, causing it to run away to the side.

Step 5: Next, you need to walk around the trees and step on the branches as shown below. This will cause the Farfetch’d to face West, allowing you to sneak up on it.

Step 6: Then backtrack so you can sneak up behind the Farfetch’d as shown below, making sure not to step on any other branches.

Step 7: After rescuing the charcoal cutter’s Pokémon, he will reward you with the HM01: Cut. Return to Azalea town and go to the house located East of the Gym.

Step 8: Speak to the NPC on the right and he will give you the Charcoal.

Method 2: The Ruins of Alph

There is a way for you to obtain an additional piece of Charcoal. It can be found in the Ruins of Alph. However, it can only be accessed by having the HM Surf and having a Ho-Oh in your party.
Step 1: Start by entering Union cave. In this guide, we will be entering through the entrance located at the bottom of Route 32.

Step 2: After entering the cave, head West. Once you reach the point pictured below, head North.

Step 3: Continue North and enter the staircase to the left. If you follow the exact path shown in the image below, you can avoid the battle with the Firebreather.

Step 4: After descending the stairs, use Surf to cross the water and head North.

Step 5: Continue heading North past the Hiker.

Step 6: Head west past the other Hiker and continue up the stairs.

Step 7: Use Surf to cross the water and head North. Then go up the staircase to the West and exit the cave.

Step 8: After exiting the cave, you will arrive at the Ruins of Alph. Defeat the Psychic standing in front of the entrance and enter the building on the right.

Step 9: After entering the building, interact with the slab in the back of the room with Ho-Oh in the first slot of your party. The wall will open, revealing a secret room.

Step 10: In the secret room, there will be four items on the floor. The top right item is the Charcoal.

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