There are several. One of them is the second cave in that route under the biycicle road thingy.
its a secret place
hes not in platinum:( try ruby
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ActionReplay
you go under ground and get the digger drill and use it to make a secret base
no
There are secret bases in Pokémon Ruby Sapphire and Emerald. In Diamond Pearl and Platinum, you have underground bases.
Theres a lot of secret places in diamond like old cave where you can find dark lugia in your first try to battle. It located in canalave city by riding a boat. It only open when you got 10 battle records with platinum. Except to dark lugia....a wild solrock can appeared in shiny. Have a nice battles with platinum
There is no specific "best place" but I think it would be best to have it in the really big area under Floroma town.
by secret event which is over... sob i missed it also
mysteri gift
its a secret place
No, you can't mix records in Pokémon Platinum in order to get the Secret Key from a friend.
You can't get the Secret Key in Pokemon Platinum without Action Replay, unfortunately. You can get Action Replay from most major websites.
hes not in platinum:( try ruby
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Valor Lakefront