Where To Get The BlackGlasses in Pokémon HGSSThis post may contain affiliate links. If you buy something we may get a small commission at no extra cost to you. (Learn more).
The only pair of BlackGlasses available in HeartGold/SoulSilver can be found in Dark Cave. You’ll need at least 7 Gym Badges to reach the part of the cave where they’re found. You’ll also need to bring a Pokémon with Surf, and one with Flash if you want to be able to see inside the cave.
Any Pokémon holding the BlackGlasses will have their Dark-Type moves boosted in power by 20%.
To obtain them, start by flying to Blackthorn City, then take the south exit onto Route 45.
From there, head south and take the first left turn.
Walk across the bridge and you’ll come to the entrance of Dark Cave.
Head inside and light up your surroundings with Flash.
Walk to the left and take the first two sets of stairs you encounter.
Shortly to the south of the second set of stairs, you’ll see a body of water. Surf on it.
Surf around to the left and dismount your Pokémon on the first patch of dry land you see, pictured below.
Follow the one-way path up north for some time until you come to an intersection. You need to take the left path here, up a small staircase.
Follow this path around and, before long, you’ll see a man wearing sunglasses.
Talk to him and he’ll make some fairly suspicious comments and then bribe you with a pair of BlackGlasses of your very own to forget you ever saw him. Seems fair enough.