In emerald you need to beat the league and in fr/lg you need to unlock all 7 of the sevii islands
Altering cave is on 5 or 6 island.
There is no Altering Cave in Pokémon Platinum.
You can't do anything with altering cave unless you have an E Reader.
There are no moveable rocks in Altering Cave.
No.
Altering Cave is found to the north of Fortune Island, on Outcast Island.
It's normally no pokémons in the altering cave i heard that you must do something ;)
to find houndour you need to unlock mystery gift and you'll need another person to play mystery gift with you and then different types of Pokemon will appear in the altering cave.
Altering cave does not change into traveler's cave. Altering cave can only offer new Pokemon (since all it offers are zubat) after using Mystery Gift.
Its is nothing it is just there..
it does not have a purpose
Zubat.