I don't think alot of you Pokemon fans, knew about the SECRET STONE. First you either need the FLY and (or) the SURF HM before you can even think about getting it. FLY or SURF to Mossdeep City, *MAKE SURE YOU HAVE 6 POKEMON*, then go all the way up to the Mossdeep City SPACE CENTER. Once you enter the SPACE CENTER, walk ALL THE WAY up to you encounter a guy with a lab-coat on, talk to them (2 times) then go down to a guy that is dresed like a SAILOR. Talk to him(make sure your ITEM BAG is not full) once you talk to him he will give a SECRET STONE, called the SUN STONE. It can be used on many pokemon except WATER,and GRASS type.

Hope i helped you.