Captain Storm, Cosmium Raider

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

Swamp

Uncharted Haven

Uncharted Haven enters tapped. As it enters, choose a color.
{T}: Add one mana of the chosen color.

Prosperous Pirates

When Prosperous Pirates enters, create two Treasure tokens. (They're artifacts with "{T}, Sacrifice this artifact: Add one mana of any color.")

Storm Fleet Pyromancer

Raid — When Storm Fleet Pyromancer enters, if you attacked this turn, Storm Fleet Pyromancer deals 2 damage to any target.

Headstrong Brute

Headstrong Brute can't block.
Headstrong Brute has menace as long as you control another Pirate.

Murder

Lookout's Dispersal

This spell costs {1} less to cast if you control a Pirate.
Counter target spell unless its controller pays {4}.

Fiery Cannonade

Fiery Cannonade deals 2 damage to each non-Pirate creature.

Deadeye Plunderers

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.")

Unknown Shores

{T}: Add {C}.
{1}, {T}: Add one mana of any color.

Essence Capture

Counter target creature spell. Put a +1/+1 counter on up to one target creature you control.

Reckless Lackey

First strike, haste
{2}{R}, Sacrifice Reckless Lackey: Draw a card and create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Arcane Signet

{T}: Add one mana of any color in your commander's color identity.

Unclaimed Territory

As Unclaimed Territory enters, choose a creature type.
{T}: Add {C}.
{T}: Add one mana of any color. Spend this mana only to cast a creature spell of the chosen type.

Fathom Fleet Captain

Menace
Whenever Fathom Fleet Captain attacks, if you control another nontoken Pirate, you may pay {2}. If you do, create a 2/2 black Pirate creature token with menace.

Wily Goblin

When Wily Goblin enters, create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Mountain

March of the Drowned

Choose one —
• Return target creature card from your graveyard to your hand.
• Return two target Pirate cards from your graveyard to your hand.

Island

Wayfarer's Bauble

{2}, {T}, Sacrifice Wayfarer's Bauble: Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Dire Fleet Hoarder

When Dire Fleet Hoarder dies, create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Dire Fleet Ravager

Menace, deathtouch
When Dire Fleet Ravager enters, each player loses a third of their life, rounded up.

Fell Flagship

Pirates you control get +1/+0.
Whenever Fell Flagship deals combat damage to a player, that player discards a card.
Crew 3 (Tap any number of creatures you control with total power 3 or more: This Vehicle becomes an artifact creature until end of turn.)

Warkite Marauder

Flying
Whenever Warkite Marauder attacks, target creature defending player controls loses all abilities and has base power and toughness 0/1 until end of turn.