How do you do the Phenac city bit?

First talk to the little boy by the entrace of the pre gym he will say that someone was going to the phenac colosseum. then go to the phenac colosseum and there will be a chiper with a nuzleaf. fight him and if you beat him go inside the colosseum. then go in the blue or green door (doesnt matter at all). there will be 2 chipers if you beat them go further there will be a camera man and marcia standing by a chiper admin he will have a shadow lunatune if you beat him he will drop a elevator key. then go to the pre gym and click on the chair by justy's desk. click on yes and the elevator will be working again

Go up the stairs where there is a man and his Pokemon, he's an under cover Cipher, so you'll of course battle. After defeting him/ her continue straight into the building. There will be two doors, a Green one and a Blue one, go in either cas they both lead to the same place. In there you will have two more battles I think, after defeting them you'll fight Admin, so heal up first, she'll drop it when your done.

Go into the colluseem in Phenac City.

You have do go to the old pre gym and defeat some guy who will drop the key

You must go to the Phenic Colloseum and beat Snattle and then you find the key where he was.

You have to go to Phenac Collosseum and beat C.A. Snattle. Note: Get his Lunatone. It will come in handy later on. When he runs away, there should be something sparkly on the ground. Go up to it, press A, and you will have the Elevator Key.

It is in the colosseum which is situated to the back side of the pre gym