You must have a rotom from Pokemon diamond/pearl/platinum and have it as the first Pokemon in you party. Then take it to the lift and rotom will let you use the lift. After the lift has stoped you should be able to change rotoms form
Chat with our AI personalities
in saffron city
beat red and go to silph co.
Because this is 3 years after the origanal, you don't get it/need it.
you don't
You cannot.