Daring Buccaneer

Oracle Text
As an additional cost to cast this spell, reveal a Pirate card from your hand or pay
.Card Rulings
1/19/2018 If an effect refers to a “[subtype] spell” or “[subtype] card,” it refers only to a spell or card that has that subtype. For example, March of the Drowned is a card that benefits Pirates and features Pirates in its illustration, but it isn’t a Pirate card.
Also, I'm laughing at the flavor text. Those pirates really have no reason to want that Immortal Sun other than "Yarr, it be treasure"