you find the basement key in the underground path
beat exacutive patral in the radio tower and he gives you the key.
The basement key is used in the Goldenrod underground. You get it while rescuing the Radio Tower from Team Rocket - specifically, after defeating a Rocket Executive disguised as the director.
you use it to open the door to the basement!
the key is in the basement
You should iook it up on youtube and do it from there
the basement
the key is in the basement of the pokemon mansion
it is in the basement in the Pokemon mantion.
its a trick its a trick
oh hai
the secret key is in the Pokemon mansion - Celadon city basement
i think it's at the basement floor on a table.