If you are lucky enough to get Wooden Plates (or something like that), you can go on nice Secret bases (Holes on the ground(you put wooden plates on it)).
You can get them on Dept. Store on a special day. Actually the same thing as Mirage Island.

My favorite one is on the path between Fortree and Mauville. There's a bridge across a river about halfway through the map, and if you sail down the river you find a tree. The left (maybe right) side has one of those huge bases with the holes Plenty of room for slides, stages, and things that explode.

Does anyone know what happens if two people who have secret bases in the same places mix records?

You can visit the secret base of your friend.
But I don't if you can do anything special in his secret base.

You can battle them there once per day, but what happens if I put my secret base in the tree I mentioned, and my friend's base is also there, and then I mix records with him? Whose secret base shows up when I walk in the tree?

Oh, good question... I have no idea actually.
Your friend is probably in your base, dunno.

I think the best secret base is on the tip of Route 121.The bush near Route 122 is what I used for my secret base.The area seems to be big although it has a hole so it has to be placed with a Solid Board.

PS : I am just new here so no pictures or stuff

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(O'.'o) Well I have this though heheh.....
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