Seals are small stickers that are able to be attached to Ball Capsules, which can in turn be attached to Poké Balls, to attain a special effect when a Pokémon comes out of them, instead of the usual flash of light. The majority of them can be purchased in the Sunyshore Market in Sunyshore City, where the selection changes daily, though there are 28 seals of letters A through Z and the exclamation point and question mark, obtained by showing Unown to a boy in Solaceon Town.
Eight seals at a time can be attached to any Ball Capsule. They can be set on the player'sPC. Where they are placed on the Ball Capsule will affect where the effect is displayed upon the Pokémon's release.