POkemon ruby red version gba?

Question

How can I get the 8th pokemon gym door to open thanx alot..?

Answer 1

in ruby red, you need to face groudon which should become bad erosion so you have to stop it, once stopping that go back to soothopolis city and the gym leader will allow you to enter the gym.

Answer 2

the game is called pokemon ruby

go to the cave of origin, face groudon (catch or defeat him) and the gym will open

Answer 3

you need to catch the groudon in the cave of origin first and the door will open.