You’ll get the Basement Key from a Team Rocket Executive who’s been impersonating the Radio Director. This Rocket Exec gives you the Basement Key after you beat them in a Pokémon Battle on the 5th floor of the Goldenrod Radio Tower.
The Basement Key is necessary to enter the Team Rocket Warehouse inside the Goldenrod Underground Tunnel. It’s used to rescue the Radio Director.
The real Radio Director is in the Basement, and he has the Card Key needed to clear out the remaining Team Rocket Executives left at the Radio Tower.
The Basement Key can only be acquired during the Team Rocket takeover of the Goldenrod Radio Tower.
Team Rocket will make their move on the tower after you’ve completed the following tasks:
- Healed the sick Ampharos in Olivine Lighthouse.
- Dismantled the Team Rocket Hideout at Mahogany Town with Lance.
- Collected seven (7) Gym Badges.
You’ll know it’s time to head to Goldenrod City because Prof. Elm calls you on the phone to warn you of trouble in the Radio Tower.
Getting the Basement Key
Getting the Basement Key starts by heading to the Goldenrod Radio Tower.
Starting at the Goldenrod City Pokémon Center, follow the main road up until you’re almost at the train tracks, then turn left.
You’ll find the Radio Tower at the end of that street.
Get ready to fight through a bunch of Team Rocket grunts as you climb to the fifth floor.
First Floor (1F)
The first stairwell (1F>2F) is all the way to the right. There’s only one Team Rocket Grunt here.
Second Floor (2F)
The second stairwell (2F>3F) is all the way to the left, past several grunts.
You’ll have to fight at least three of them to get there.
Third Floor (3F)
Three more Rockets are waiting on the third floor, but you only need to fight the one guarding the stairs leading to 4F if you follow the right route.
Fourth Floor (4F)
Finally, go up the stairs on the top left corner (4F>5F) to reach our destination.
There are two enemy trainers in 4F, but only the Scientist is unavoidable. Watch out for his Lv. 30 Porygon!
The Rocket Grunt to the right is spinning clockwise. If you time your moves right, you can easily walk past him.
Fifth Floor (5F)
Upon reaching the fifth floor, a cutscene will play where the fake Radio Director reveals himself to be a Team Rocket Executive.
Defeat him in battle to get the Basement Key.
Tip: His team is pure Poison, so a Ground or Psychic-type Pokémon (or at least some moves of these types) in your party would make things a lot easier.
What Does the Basement Key Open?
The Basement Key is necessary to enter the Team Rocket Warehouse in the Goldenrod Underground.
You’ll do this to liberate the real Radio Director and acquire the Card Key needed to drive out the last remaining Rockets from the Radio Tower.
Tip: Don’t forget to pick up TM35 Sleep Talk while you’re there!