Migerat it or trade it. You can't use the cheat card on Pokemon platinum.
Have your friends Pokemon hold the member card and trade it.
You can only get the secret key in Pokemon Platinum
The black card is your trainer card with I think 5 stars
The card key in Pokemon Heartgold and Soulsilver is located in the Goldenrod Underground.
It is out in 2010 Pokemon Platinum
Pokemon event
Where to FIND the key card in Pokemon platinum was your question right ? well I looked for it on my game but couldn't find it. I think you mean galatic card,secret key. Secert key: location wifi galatic key; get it in building when battling someone
Migerat it or trade it. You can't use the cheat card on Pokemon platinum.
In Pokemon Platinum you dont get the key from a grunt you get from the detective, before getting the key you have to go talk to prof. rowan in the library .
the answer is clear.Hack.
Have your friends Pokemon hold the member card and trade it.
go on Pokemon Platinum Walkthrough you'll might get the idea.
i think its when you have a member card
You can only get the secret key in Pokemon Platinum
its easy but hard
you need wifi do get it!