How does scyther evolve?

Scyther will only evolve when you get a metal coat from the steel type gym leader, you can only obtained it when you defeat the elite four, after you defeated them all, even Cynthia, you can go to canalve city, you ask the boat guy to take you to iron island, you go to the house (the only house) and Bryon will give you a metal coat , also if you go to eterna city, when you go down to the cycling road you will see a house on the left, and if i do my calculations right, and most of the time i do get them right professor oak will be there and you obtained the up-grade, which you can use on a porygon,you will also need to go to i think route 225 you will find a doubulus disk for your porygon 2 (HINT)(you need to trade your porygon for porygon 2 to porygon z)