Ixalan

Deadeye Plunderers | Creature | Human Pirate | Deadeye Plunderers gets +1/+1 for each artifact you control. {2}{U}{B}: Create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.") | Greg Opalinski

Hostage Taker | Creature | Human Pirate | When Hostage Taker enters the battlefield, exile another target creature or artifact until Hostage Taker leaves the battlefield. You may cast that card for as long as it remains exiled, and you may spend mana as though it were mana of any type to cast that spell. | Wayne Reynolds

Admiral Beckett Brass | Legendary Creature | Human Pirate | Other Pirates you control get +1/+1. At the beginning of your end step, gain control of target nonland permanent controlled by a player who was dealt combat damage by three or more Pirates this turn. | Jason Rainville