if you give them to an arceus the arceus would change types, for example a flame plate would obviously make him a fire type!
Plates also power up moves of their type.
You can get some plates from the SS. Aqua captain
on the ss anne the captain gives it to you but before you can enter the captain's room you must battle your rival
you go on the SS Aqua go talk to the Captain and he'll give you a variety of plates
it is a boat that you go to the captain and rub his back and he gives you the hm cut
W. J. Roberts was the captain of the SS city of new york
He will appear just as you are about to see the Captain of the SS Anne.
John Gray
In the place where the SS tidal is.
you get it from the captain on the SS Anne cruise ship but you need the SS ticket from Bill first
Head to slateport city and go to the SS tidal captain stern will be nearby.
you have to find the captain who will give you the cut hm
Why r u asking me!?!?!?!