Loyal Inventor

Vigilance
When Loyal Inventor enters, you may search your library for an artifact card, reveal it, then shuffle. Put that card into your hand if you control an Assassin. Otherwise, put that card on top of your library.

Captain Storm, Cosmium Raider

Whenever an artifact you control enters, put a +1/+1 counter on target Pirate you control.

Admiral Beckett Brass

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.

Mary Read and Anne Bonny

Haste
{T}: Draw a card, then discard a card.
Whenever you discard an Island, Pirate, or Vehicle card, create a tapped Treasure token.

Captain Lannery Storm

Haste
Whenever Captain Lannery Storm attacks, create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")
Whenever you sacrifice a Treasure, Captain Lannery Storm gets +1/+0 until end of turn.

Hostage Taker

When Hostage Taker enters, 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 mana of any type can be spent to cast that spell.

The Indomitable

Trample
Whenever a creature you control deals combat damage to a player, draw a card.
Crew 3
You may cast The Indomitable from your graveyard as long as you control three or more tapped Pirates and/or Vehicles.

Adéwalé, Breaker of Chains

When Adéwalé enters, reveal the top six cards of your library. Put an Assassin, Pirate, or Vehicle card from among them into your hand and the rest on the bottom of your library in a random order.
Whenever a Vehicle you control deals combat damage to a player, you may return Adéwalé from your graveyard to your hand.

Jackdaw

Whenever Jackdaw deals combat damage to a player, you may discard your hand. If you do, draw a card for each artifact you control.
Crew 3

Edward Kenway

At the beginning of your end step, create a Treasure token for each tapped Assassin, Pirate, and/or Vehicle you control.
Whenever a Vehicle you control deals combat damage to a player, look at the top card of that player's library, then exile it face down. You may play that card for as long as it remains exiled.

The Belligerent

Whenever The Belligerent attacks, create a Treasure token. Until end of turn, you may look at the top card of your library any time, and you may play lands and cast spells from the top of your library.
Crew 3

Adrestia

Islandwalk (This creature can't be blocked as long as defending player controls an Island.)
Whenever Adrestia attacks, if an Assassin crewed it this turn, draw a card. Adrestia becomes an Assassin in addition to its other types until end of turn.
Crew 1