what are the rare items in pokemon go?
['Dragon Scale: Evolves Seadra into Kingdra.', "King's Rock: Evolves Poliwhirl into Politoed and Slowpoke into Slowking.", 'Metal Coat: Evolves Onix into Steelix and Scyther into Scizor.', 'Sun Stone: Evolves Gloom into Bellossom and Sunkern into Sunflora.']