Yes - it's called Area 51! But as secret bases go, an awful lot of people seem to know about it... (Õ.ô)
There are secret bases in Pokémon Ruby Sapphire and Emerald. In Diamond Pearl and Platinum, you have underground bases.
No
of course
they are secret bases you need to teach a Pokemon secret power first to use them
Those are secret bases to create one use the move secret power.
Those are secret bases to create one use the move secret power.
You need to steal the flag out of your friend's Secret Base underground, then go up to the PC.
NO NO NO NOO
You can put plants in your secret bases in emerald
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Secret power can make secret bases for you find a tree or bush or indent in a wall then use secret power on it and inside is a base this is a place where you can decorate and customize your own place! Also if you mix records with other ruby and sapphire and emerald games you can battle other peoples secret bases! Secret power also can inflict opponents Pokemon with poison, flinch, parlyze, sleep, and can lower stats like speed.
Traveling north on route 111 (north of the desert), you should see a boy (man?) looking at a tree. He will give you the TM for Secret Power. Give secert power to a pokemon and now you should be able to make secret bases! Now simply look at any large tree, bush, or cracked wall and use secret power! And there you have it. Your own secret base.